scholarly journals Age-Based Survival Analysis of Coniferous and Broad-Leaved Trees: A Case Study of Preserved Forests in Northern Japan

Forests ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 1014
Author(s):  
Pavithra Rangani Wijenayake ◽  
Takuya Hiroshima
Keyword(s):  
Natural Forest ◽  
Natural Forests ◽  
Individual Tree ◽  
Coniferous Species ◽  
Survival Analyses ◽  
Diameter At Breast Height ◽  
Survival Probabilities ◽  
Breast Height ◽  
Broad Leaved Species ◽  
Mean Lifetimes

Scientifically sound methods are essential to estimate the survival of trees, as they can substantially support sustainable management of natural forest resources. Tree mortality assessments have mainly been based on forest inventories and are mostly limited to planted forests; few studies have conducted age-based survival analyses in natural forests. We performed survival analyses of individual tree populations in natural forest stands to evaluate differences in the survival of two coniferous species (Abies sachalinensis (F. Schmidt) Mast. and Picea jezoensis var. microsperma) and all broad-leaved species. We used tree rings and census data from four preserved permanent plots in pan-mixed and sub-boreal natural forests obtained over 30 years (1989–2019). All living trees (diameter at breast height ≥ 5 cm in 1989) were targeted to identify tree ages using a Resistograph. Periodical tree age data, for a 10-year age class, were obtained during three consecutive observation periods. Mortality and recruitment changes were recorded to analyze multi-temporal age distributions and mean lifetimes. Non-parametric survival analyses revealed a multi-modal age distribution and exponential shapes. There were no significant differences among survival probabilities of species in different periods, except for broad-leaved species, which had longer mean lifetimes in each period than coniferous species. The estimated practical mean lifetime and diameter at breast height values of each coniferous and broad-leaved tree can be applied as an early identification system for trees likely to die to facilitate the Stand-based Silvicultural Management System of the University of Tokyo Hokkaido Forest. However, the survival probabilities estimated in this study should be used carefully in long-term forest dynamic predictions because the analysis did not include the effects of catastrophic disturbances, which might significantly influence forests. The mortality patterns and survival probabilities reported in this study are valuable for understanding the stand dynamics of natural forests associated with the mortality of individual tree populations.

Modelling survival probability of individual trees in Norway spruce stands under different thinning regimes

2005 ◽  
Vol 35 (1) ◽  
pp. 113-121 ◽  
Author(s):  
Kjell Karlsson ◽  
Lennart Norell
Keyword(s):  
Norway Spruce ◽  
Goodness Of Fit ◽  
Basal Area ◽  
Site Index ◽  
Stand Age ◽  
Goodness Of Fit Test ◽  
Individual Tree ◽  
Thinning Intensity ◽  
Diameter At Breast Height ◽  
Breast Height

The probability that an individual tree will remain in even-aged Norway spruce (Picea abies (L.) Karst.) stands subjected to different thinning programmes was modelled, using data from a thinning experiment established in 25 localities in southern Sweden. A logistic regression approach was used to predict the probability and the Hosmer–Lemeshow goodness-of-fit test to evaluate the fit. Diameter at breast height (DBH), quadratic mean DBH, thinning intensity, thinning quotient, basal area, number of stems per hectare, stand age, number of thinnings, and site index were used as explanatory variables. Separate analyses for stands thinned from below, stands thinned from above, and unthinned stands were performed. The modelled probability graphs for trees not being removed, plotted against their diameter at breast height, had clear S-shapes for both unthinned stands and stands thinned from below. The graph for stands thinned from above was bell-shaped.

scholarly journals Point-cloud segmentation of individual trees in complex natural forest scenes based on a trunk-growth method

2021 ◽  
Author(s):  
Qianwei Liu ◽  
Weifeng Ma ◽  
Jianpeng Zhang ◽  
Yicheng Liu ◽  
Dongfan Xu ◽  
...  
Keyword(s):  
Point Cloud ◽  
Laser Scanning ◽  
Plant Morphology ◽  
Natural Forest ◽  
Normal Vector ◽  
Natural Forests ◽  
Individual Tree ◽  
Single Tree ◽  
Point Cloud Segmentation ◽  
Individual Trees

AbstractForest resource management and ecological assessment have been recently supported by emerging technologies. Terrestrial laser scanning (TLS) is one that can be quickly and accurately used to obtain three-dimensional forest information, and create good representations of forest vertical structure. TLS data can be exploited for highly significant tasks, particularly the segmentation and information extraction for individual trees. However, the existing single-tree segmentation methods suffer from low segmentation accuracy and poor robustness, and hence do not lead to satisfactory results for natural forests in complex environments. In this paper, we propose a trunk-growth (TG) method for single-tree point-cloud segmentation, and apply this method to the natural forest scenes of Shangri-La City in Northwest Yunnan, China. First, the point normal vector and its Z-axis component are used as trunk-growth constraints. Then, the points surrounding the trunk are searched to account for regrowth. Finally, the nearest distributed branch and leaf points are used to complete the individual tree segmentation. The results show that the TG method can effectively segment individual trees with an average F-score of 0.96. The proposed method applies to many types of trees with various growth shapes, and can effectively identify shrubs and herbs in complex scenes of natural forests. The promising outcomes of the TG method demonstrate the key advantages of combining plant morphology theory and LiDAR technology for advancing and optimizing forestry systems.

A simplified tree bait for the mountain pine beetle

1993 ◽  
Vol 23 (6) ◽  
pp. 1108-1113 ◽  
Author(s):  
J.H. Borden ◽  
L.J. Chong ◽  
B.S. Lindgren ◽  
E.J. Begin ◽  
T.M. Ebata ◽  
...  
Keyword(s):  
Release Rate ◽  
Mountain Pine Beetle ◽  
Diameter Class ◽  
Individual Tree ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Mountain Pine ◽  
Pine Beetle ◽  
Antiaggregation Pheromone ◽  
And Control

Seven, split-block experiments throughout British Columbia in 1989 tested the efficacy of binary tree baits containing the pheromones trans-verbenol and exo-brevicomin or ternary baits with the addition of the host tree kairomone myrcene for containing and concentrating infestations of the mountain pine beetle, Dendroctonusponderosae Hopkins, in stands of lodgepole pine, Pinuscontorta var. latifolia Engelm. Attack densities on baited trees, attack frequencies of baited trees and trees within 10 m of the baited trees, and the ratios of newly attacked, green, trees to previously attacked, red, trees were generally statistically equal between sub-blocks containing binary or ternary baits. Where statistically significant differences occurred for one or more of the above criteria in one experiment, they were generally offset by statistically significant differences in the opposite direction in another experiment. Two individual-tree experiments in 1990 that supported the equality of binary and ternary baits indicated that raising the release rate of trans-verbenol in binary baits tended to reduce their efficacy (possibly because of contamination with the antiaggregation pheromone verbenone) and showed that increasing the release rate of exo-brevicomin tended to counteract this effect. When attack frequencies were subdivided by diameter class of available trees attacked, all baits were effective in inducing attack on available trees <30.0 cm diameter at breast height (1.3 m), but attack on baited and control trees ≥30 cm diameter at breast height was equal. Provided that the trans-verbenol in binary baits does not contain or autoxidize to verbenone, myrcene can be deleted from operational tree baits.

scholarly journals Allometric equations for estimating biomass of community forest tree species in Madiun, Indonesia

2020 ◽  
Vol 21 (9) ◽  
Author(s):  
Pandu Wirabuana ◽  
RAHMANTA SETIAHADI ◽  
RONGGO SADONO ◽  
MARTIN LUKITO ◽  
DJOKO SETYO MARTONO ◽  
...  
Keyword(s):  
Tree Species ◽  
Forest Tree ◽  
Allometric Equations ◽  
Tree Biomass ◽  
Community Forest ◽  
Individual Tree ◽  
Community Forests ◽  
Forest Tree Species ◽  
Diameter At Breast Height ◽  
Breast Height

Abstract. Wirabuana PYAP, Setiahadi R, Sadono R, Lukito M, Martono DS, Matatula J. 2020. Allometric equations for estimating biomass of community forest tree species in Madiun, Indonesia. Biodiversitas 21: 4291-4300. The capability of community forests for offsetting carbon emissions highly depends on their biomass production. Unfortunately, the measurement of tree biomass in community forests using a destructive method is expensive and time-consuming. It is also almost impossible to conduct this method for all trees in the observation area. Therefore, the development of allometric equations is essential to support tree biomass estimation in community forests. This study was designed to construct specific models for predicting individual tree biomass in community forests, located in Madiun, Indonesia. We destructively sampled approximately 120 trees from four different species (30 trees for each species), i.e., Falcataria moluccana, Melia azedarach, Swietenia macrophylla, and Tectona grandis. For every tree sample, the measurement of biomass was conducted in each tree’s component, namely roots, stem, branches, and leaves. The allometric equations were developed with regression analysis using predictor variables, like diameter at breast height (D), squared diameter at breast height combined with tree height (D2H), as well as D and H separately. Results found that for four species, the mean biomass in the stem was 50.3%, followed by branches 25.4%, roots 15.9%, and leaves 8.3%. The best equation for estimating biomass in every component and total of four species was different. However, our study showed that the equation lnŶ = -3.037 + 1.430 lnD + 1.684 was reliable to estimate total individual tree biomass of four species in the surveyed area since this model had accuracy of 90.8%. Referring to these findings, we recommended the utilization of an allometric equation as an alternative method for facilitating more efficient biomass measurement in the community forests.

Application of probability distribution in order to fit the diameter and height of oak species in two natural and man-made stands in Hyrcanian forests

2016 ◽  
Vol 09 (03) ◽  
pp. 1650048
Author(s):  
Farah Mohammadi ◽  
Mir Mozaffar Fallahchai ◽  
Seyed Armin Hashemi
Keyword(s):  
Probability Distribution ◽  
Statistical Distributions ◽  
Sample Plot ◽  
Weibull Distributions ◽  
Natural Forests ◽  
Diameter At Breast Height ◽  
Hyrcanian Forests ◽  
Breast Height ◽  
Oak Trees

In order to study the fitting of some characteristics like low diameter at breast height (DBH), the height and height to the beginning of crown of the Oak species in two man-made and natural forests of this species in north of Guilan’s forests, Tooshi and Radarposhte forests were selected. A 100% inventory was done on a one-hectare sample plot in Tooshi man-made forests and on a two-hectare sample plot in Radarposhte natural forests. The results from this study showed that, in order to fit the diameter and the height of the Oak trees in man-made stands, Johnson’s S[Formula: see text] and normal statistical distributions have more capabilities and the three-parameter gamma and the three-parameter Weibull distributions are appropriate for diameters and heights of the natural Oak trees in Radarposhte forest, respectively.

scholarly journals Estimating Individual Tree Height and Diameter at Breast Height (DBH) from Terrestrial Laser Scanning (TLS) Data at Plot Level

Forests ◽  
2018 ◽  
Vol 9 (7) ◽  
pp. 398 ◽  
Author(s):  
Guangjie Liu ◽  
Jinliang Wang ◽  
Pinliang Dong ◽  
Yun Chen ◽  
Zhiyuan Liu
Keyword(s):  
Laser Scanning ◽  
Terrestrial Laser Scanning ◽  
Tree Height ◽  
Individual Tree ◽  
Diameter At Breast Height ◽  
Breast Height

scholarly journals Allometric Equations for Estimating Aboveground Biomass of Eucalyptus urophylla S.T. Blake in East Nusa Tenggara

2021 ◽  
Vol 27 (1) ◽  
pp. 24-31
Author(s):  
R Sadono ◽  
◽  
W Wahyu ◽  
F Idris
Keyword(s):  
Aboveground Biomass ◽  
Tree Height ◽  
Allometric Equation ◽  
Allometric Equations ◽  
Accurate Estimation ◽  
Eucalyptus Urophylla ◽  
Individual Tree ◽  
Eucalyptus Plantation ◽  
Diameter At Breast Height ◽  
Breast Height

Understanding the essential contribution of eucalyptus plantation for industry development and climate change mitigation requires the accurate quantification of aboveground biomass at the individual tree species level. However, the direct measurement of aboveground biomass by destructive method is high cost and time consuming. Therefore, developing allometric equations is necessary to facilitate this effort. This study was designed to construct the specific allometric models for estimating aboveground biomass of Eucalyptus urophylla in East Nusa Tenggara. Forty two sample trees were utilized to develop allometric equations using regression analysis. Several parameters were selected as predictor variables, i.e. diameter at breast height (D), quadrat diameter at breast height combined with tree height (D2H), as well as D and H separately. Results showed that the mean aboveground biomass of E. urophylla was 143.9 ± 19.44 kg tree-1. The highest biomass were noted in stem (80.06%), followed by bark (11.89%), branch (4.69%), and foliage (3.36%). The relative contribution of stem to total aboveground biomass improved with the increasing of diameter class while the opposite trend was recorded in bark, branch, and foliage. The equation lnŶ = lna + b lnD was best and reliable for estimating the aboveground biomass of E. urophylla since it provided the highest accurate estimation (91.3%) and more practical than other models. Referring to these findings, this study concluded the use of allometric equation was reliable to support more efficient forest mensuration in E. urophylla plantation.

scholarly journals An individual-tree linear mixed-effects model for predicting the basal area increment of major forest species in Southern Europe

2020 ◽  
Vol 29 (3) ◽  
pp. e019
Author(s):  
Lucio Di Cosmo ◽  
Diego Giuliani ◽  
Maria Michela Dickson ◽  
Patrizia Gasparini
Keyword(s):  
Forest Inventory ◽  
Basal Area ◽  
Ordinary Least Squares ◽  
Mixed Effects ◽  
Forest Growth ◽  
Mixed Effects Model ◽  
Basal Area Increment ◽  
Individual Tree ◽  
Diameter At Breast Height ◽  
Breast Height

Aims of the study. Assessment of growth is essential to support sustainability of forest management and forest policies. The objective of the study was to develop a species-specific model to predict the annual increment of tree basal area through variables recorded by forest surveys, to assess forest growth directly or in the context of more complex forest growth and yield simulation models.Area of the study. Italy.Material and methods. Data on 34638 trees of 31 different forest species collected in 5162 plots of the Italian National Forest Inventory were used; the data were recorded between 2004 and 2006. To account for the hierarchical structure of the data due to trees nested within plots, a two-level mixed-effects modelling approach was used.Main results. The final result is an individual-tree linear mixed-effects model with species as dummy variables. Tree size is the main predictor, but the model also integrates geographical and topographic predictors and includes competition. The model fitting is good (McFadden’s Pseudo-R2 0.536), and the variance of the random effect at the plot level is significant (intra-class correlation coefficient 0.512). Compared to the ordinary least squares regression, the mixed-effects model allowed reducing the mean absolute error of estimates in the plots by 64.5% in average.Research highlights. A single tree-level model for predicting the basal area increment of different species was developed using forest inventory data. The data used for the modelling cover 31 species and a great variety of growing conditions, and the model seems suitable to be applied in the wider context of Southern Europe.   Keywords: Tree growth; forest growth modelling; forest inventory; hierarchical data structure; Italy.Abbreviations used: BA - basal area; BAI – five-year periodic basal area increment; BALT - basal area of trees larger than the subject tree; BASPratio - ratio of subject tree species basal area to stand basal area; BASTratio - ratio of subject tree basal area to stand basal area; CRATIO - crown ratio; DBH – diameter at breast height ; DBH0– diameter at breast height corresponding to five years before the survey year; DBHt– diameter at breast height measured in the survey year; DI5 - five-year, inside bark, DBH increment; HDOM - dominant height; LULUCF - Land Use, Land Use Changes and Forestry; ME - mean error; MAE - mean absolute error; MPD - mean percent deviation; MPSE - mean percent standard error; NFI(s) - National Forest Inventory/ies; OLS - ordinary least squares regression; RMSE - root mean squared error; UNFCCC - United Nation Framework Convention on Climate Change.

The Relationship of Diameter at Breast Height and Crown Diameter for Four Species Groups in Hardin County, Tennessee

1995 ◽  
Vol 19 (4) ◽  
pp. 177-181 ◽  
Author(s):  
Lawrence R. Gering ◽  
Dennis M. May
Keyword(s):  
Field Measurements ◽  
Aerial Photographs ◽  
Linear Regression Models ◽  
Individual Tree ◽  
Diameter At Breast Height ◽  
Crown Diameter ◽  
Breast Height ◽  
Forest Experiment Station ◽  
Species Groups ◽  
Time Required

Abstract A set of simple linear regression models for predicting diameter at breast height (dbh) from crown diameter and a set of similar models for predicting crown diameter from dbh were developed for four species groups in Hardin County, TN. Data were obtained from 557 trees measured during the 1989 USDA Southern Forest Experiment Station survey of the forests of Tennessee, with supplemental aerial photographic observations. Estimates of individual tree crown diameter were obtained from ground measurements and from measurements made on 9 X 9 in. color aerial photographs (with nominal scale of 1:4,800) taken during the fall color season. In practice, users of aerial photographs can estimate dbh by measuring crown diameter, converting it to feet using the photo scale, and applying the appropriate equation. Similarly, crown diameter can be estimated from a ground measurement of dbh. This procedure may be useful in reducing the time required for field measurements. It may also be used to calculate crown diameters for datasets that include dbh but no direct measurement of crown attributes. South. J. Appl. For. 19(4):177-181.

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