A Comparative Evaluation of Three Stem Profile Equations for Three Precious Tree Species in Southern China

Accurately describing the stem curve of precious tree species and estimating the quantity of various types of wood and their volume in the tropics can provide technical support for reasonable bucking. This study utilized Erythrophleum fordii, Castanopsis hystrix and Tectona grandis as study objects. Forty replicates of each species were used for a total of 120 individual trees. Their tape equations were constructed using simple tape equations, segmented taper equations and variable form taper equations. Statistical indicators were utilized to determine the best taper equation for the three types of precious tree species. A number of methods were compared and analyzed, including the index of correlation, the residual sum of squares, the mean prediction error, the variance of prediction errors and the root mean square error. Finally, a preliminary quantitative analysis was conducted to determine the trends of these three types of tree species. The result shows that the precision of the three predictions developed for each species is high, and, in particular, the segmented taper equations with optimized algorithms is the best. The tendency of the three species to vary was shown to be the highest for T. grandis in the range of 0.0 to 0.8 for its relative height, followed by E. fordii, while the variation of C. hystrix was the smallest. However, in the range of 0.8 to 1.0 relative height, the variation of Castanopsis hystrix was the largest, and the variation of both E. fordii and T. grandis were almost the same. Therefore, the segmented taper equations with optimization algorithms was recommended to fit the three types of tree species in the tropics. These types of equations can be used to estimate the stumpage and timber quantity and as a guide reasonable bucking for these three species.

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Variable-Exponent Taper Equation Based on Multilevel Nonlinear Mixed Effect for Chinese Fir in China

Forests ◽

10.3390/f12020126 ◽

2021 ◽

Vol 12 (2) ◽

pp. 126

Author(s):

Sensen Zhang ◽

Jianjun Sun ◽

Aiguo Duan ◽

Jianguo Zhang

Keyword(s):

Variable Exponent ◽

Southern China ◽

Information Criteria ◽

Chinese Fir ◽

Tree Level ◽

Mixed Effect ◽

Basic Model ◽

Taper Equation ◽

Taper Equations ◽

Taper Models

A variable-exponent taper equation was developed for Chinese fir (Cunninghamia lanceolate (Lamb.) Hook.) trees grown in southern China. Thirty taper equations from different groups of models (single, segmented, or variable-exponent taper equation) were compared to find the excellent basic model with S-plus software. The lowest Akaike information criteria (AIC), Bayesian information criteria (BIC), and -2loglikelihood (-2LL) was chosen to determine the best combination of random parameters. Single taper models were found having the lowest precision, and the variable-exponent taper equations had higher precision than the segmented taper equations. Four variable-exponent taper models that developed by Zeng and Liao, Bi, Kozak, Sharma, and Zhang respectively, were selected as basic model and had no difference in fit statistics between them. Compared with the model without seldom parameter, the nonlinear mixed-effects (NLME) model improves the fitting performance. The plot-level NLME model was found not to remove the residual autocorrelation. The tree-level and two-level NLME model had better simulation accuracy than the plot-level NLME model, and there were no significant differences between the tree-level and two-level NLME model. Variable-exponent taper model developed by Kozak showed the best performance while considering two-level or tree-level NLME model, and produced better predictions for medium stems compared to lower and upper stems.

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Development of a stem taper equation and modelling the effect of stand density on taper for Chinese fir plantations in Southern China

PeerJ ◽

10.7717/peerj.1929 ◽

2016 ◽

Vol 4 ◽

pp. e1929 ◽

Cited By ~ 3

Author(s):

Aiguo Duan ◽

Sensen Zhang ◽

Xiongqing Zhang ◽

Jianguo Zhang

Keyword(s):

Predictive Accuracy ◽

Southern China ◽

Model Development ◽

Stand Density ◽

Chinese Fir ◽

Planting Density ◽

Jiangxi Province ◽

Stem Taper ◽

Taper Equation ◽

Taper Equations

Chinese fir (Cunninghamia lanceolata) is the most important commercial tree species in southern China. The objective of this study was to develop a variable taper equation for Chinese fir, and to quantify the effects of stand planting density on stem taper in Chinese fir. Five equations were fitted or evaluated using the diameter-height data from 293 Chinese fir trees sampled from stands with four different densities in Fenyi County, Jiangxi Province, in southern China. A total of 183 trees were randomly selected for the model development, with the remaining 110 trees used for model evaluation. The results show that the Kozak’s, Sharma/Oderwald, Sharma/Zhang and modified Brink’s equations are superior to the Pain/Boyer equation in terms of the fitting and validation statistics, and the modified Brink’s and Sharma/Zhang equations should be recommended for use as taper equations for Chinese fir because of their high accuracy and variable exponent. The relationships between some parameters of the three selected equations and stand planting densities can be built by adopting some simple mathematical functions to examine the effects of stand planting density on tree taper. The modelling and prediction precision of the three taper equations were compared with or without incorporation of the stand density variable. The predictive accuracy of the model was improved by including the stand density variable and the mean absolute bias of the modified Brink’s and Sharma/Zhang equations with a stand density variable were all below 1.0 cm in the study area. The modelling results showed that the trees have larger butt diameters and more taper when stand density was lower than at higher stand density.

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Using Discrete-Point LiDAR to Classify Tree Species in the Riparian Pacific Northwest, USA

Remote Sensing ◽

10.3390/rs13142647 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2647

Author(s):

Julia Tatum ◽

David Wallin

Keyword(s):

Pacific Northwest ◽

Tree Species ◽

3D Structure ◽

Alnus Rubra ◽

Populus Balsamifera ◽

Segmentation Method ◽

Black Cottonwood ◽

Riparian Landscape ◽

Individual Trees ◽

Species Mapping

Practical methods for tree species identification are important for both land management and scientific inquiry. LiDAR has been widely used for species mapping due to its ability to characterize 3D structure, but in structurally complex Pacific Northwest forests, additional research is needed. To address this need and to determine the feasibility of species modeling in such forests, we compared six approaches using five algorithms available in R’s lidR package and Trimble’s eCognition software to determine which approach most consistently identified individual trees across a heterogenous riparian landscape. We then classified segments into Douglas fir (Pseudotsuga menziesii), black cottonwood (Populus balsamifera ssp. trichocarpa), and red alder (Alnus rubra). Classification accuracies based on the best-performing segmentation method were 91%, 92%, and 84%, respectively. To our knowledge, this is the first study to investigate tree species modeling from LiDAR in a natural Pacific Northwest forest, and the first to model Pacific Northwest species at the landscape scale. Our results suggest that LiDAR alone may provide enough information on tree species to be useful to land managers in limited applications, even under structurally challenging conditions. With slight changes to the modeling approach, even higher accuracies may be possible.

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Characterizing Tree Species of a Tropical Wetland in Southern China at the Individual Tree Level Based on Convolutional Neural Network

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing ◽

10.1109/jstars.2019.2950721 ◽

2019 ◽

Vol 12 (11) ◽

pp. 4415-4425 ◽

Cited By ~ 2

Author(s):

Ying Sun ◽

Qinchuan Xin ◽

Jianfeng Huang ◽

Bo Huang ◽

Hongsheng Zhang

Keyword(s):

Neural Network ◽

Convolutional Neural Network ◽

Tree Species ◽

Southern China ◽

Tree Level ◽

Individual Tree ◽

The Individual

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Modelling growing space of four valuable broadleaved tree species in southern China

Forest Science and Practice ◽

10.1007/s11632-013-0301-z ◽

2013 ◽

Vol 15 (3) ◽

pp. 167-178

Author(s):

Johanna Schuler ◽

Josephine Cueni ◽

Heinrich Spiecker ◽

Wen-Fu Guo

Keyword(s):

Tree Species ◽

Southern China ◽

Broadleaved Tree Species ◽

Broadleaved Tree

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ASSESSMENT OF AIR POLLUTION TOLERANCE INDEX OF PLANTS: A COMPARATIVE STUDY

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2017v9i7.18447 ◽

2017 ◽

Vol 9 (7) ◽

pp. 83 ◽

Cited By ~ 4

Author(s):

Aasawari A. Tak ◽

Umesh B. Kakde

Keyword(s):

Air Pollution ◽

Azadirachta Indica ◽

Tree Species ◽

Tectona Grandis ◽

Acacia Nilotica ◽

Tolerance Index ◽

Tamarindus Indica ◽

Cassia Fistula ◽

Pollution Tolerance ◽

Air Pollution Tolerance Index

Objective: Air pollution is one of the major global tribulations in many developing cities around the world. Addressing this sort of pollution is more intricate than other ecological challenges. As pollution is an upcoming issue, we aimed at assessing the air pollution tolerant plants from roadside exposed to vehicular air pollution from two different locations in Thane city.Methods: In the present study, commonly available ten roadside tree species selected from polluted and control area, and their air pollution tolerance index (APTI) determined in Thane city. The biochemical parameters viz. pH, ascorbic acid, total chlorophyll, relative water content (RWC) were considered to calculate APTI by using standard method.Results: The study shows that the control site has more APTI than the polluted site. The APTI observed minimum in Tectona grandis 5.2±0.3247 and maximum in Azadirachta indica 13.5±0.4404. Reduction in APTI at polluted site shows that Alstonia scholaris (6.6%), Tamarindus indica (8.8%) and Azadirachta indica (10.3%) were the most tolerant tree species, while Tectona grandis (47.5%), Acacia nilotica (27.4%) and Cassia fistula (20.7%) were more sensitive tree species. The results showed the order of tolerance (% difference in APTI) as Alstonia scholaris (6.6%)>Tamarindus indica (8.8%)>Azadirachta indica (10.3%)>Moringa pterygosperma (11.9%)>Mangifera indica (13.9%)>Bahunia variegate (14.3%)>Annona squamosa (18.7%)>Cassia fistula (20.7%)>Acacia nilotica (27.4%)>Tectona grandis (47.5%).Conclusion: Tolerant trees species can serve as a sink, and sensitive tree species can act as an indicator for air pollution mitigation. Thus, this study provides useful insights for selecting tolerant species for future planning and Greenbelt development in urban areas.

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General regularities of height-diameter curves in Hungarian oak, sessile oak and Turkey oak high forests

Silva Balcanica ◽

10.3897/silvabalcanica.21.e56074 ◽

2020 ◽

Vol 21 (2) ◽

pp. 71-82

Author(s):

Roumen Petrin

Keyword(s):

Tree Species ◽

Oak Forests ◽

Relative Height ◽

Sessile Oak ◽

Turkey Oak

The height-diameter curves of natural even-aged Hungarian oak, sessile oak and Turkey oak forests in the regions of Staro Oryahovo, Sherba, Tsonevo and Aytos Forestry Districts have been studied. In order to explore the shape of the curves and, in particular, their steepness, the steepness index SI of Douhovnikov (“the method of natural indicators”) was applied. The curves were divided into three groups according to it: flat curves, medium steep curves and steep curves. Both the traditional height-diameter curves and the corresponding relative curves of Tyurin were studied. Consideration of the traditional height-diameter curves gives a certain ground for investigating to-gether the height-diameter curves of Hungarian oak and sessile oak, disregarding the tree species. This inference was confirmed by comparing the relative height-diameter curves for Hungarian oak, sessile oak and Turkey oak with Tyurin’s uniform curve of relative heights. For these comparisons we used the Willcoxon test. A statistically significant great proximity in their shapes was found. As a uniform average curve of relative heights has been established for all tree species, this proximity indicates a possibility of creating a single fan of height-diameter curves for high Hungarian, sessile and Turkey oak.

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