• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.113-123
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• 2001

The main purpose of this study was to provide information on attenuation effects in forest tree belt of pine stand and oak stand. The relationships between DBH, tree height, clear length, crown area and number of trees and also between distance from noise origin, landslope etc. were analysed by correlation and multiple regression. The results obtained were as follows : 1. There was no difference between pine stand and oak stand in effecting noise attenuation. 2. The noise pressure was highly correlated with all of seven elements tested and both DBH and distance from noise origin have higher r-values than the others. For the pine stand, it was 0.9133 in DBH and 0.9630 in the distance and for the oak stand, 0.9296 in DBH and 0.9565 in the distance. 3. The optimum regression equation for pine stand and oak stand were made by combination of two variables (DBH and distance). The table of noise attenuation was made by optimum regression equation. In the case of pine stand, the attenuation ratio was 29% at 5m, 31.6~32.6% at 10m, 38.3~39.8% at 20m and 45.2~46.6% at 30m. And case of oak stand, the attenuation ratio was 29% at 5m, 31.6~34.2% at 10m, 38.6~41.4% at 20m and 45~47.2% at 30m. 4. As the noise pressure limit at the Urban housing area according to environmental laws is under 55dB, it is suggested by the table of noise attenuation that the distance, and DBH for the pine and oak stand are over 20m, 400cm and 30-35 trees, respectively.

• Korean Journal of Breeding Science
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• v.41 no.3
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• pp.228-235
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• 2009

Growth and branch characteristics of 35 half-sib families were surveyed in a seedling seed orchard of Quercus acutissima at ages 10 and 12. The averages of height, DBH (diameter at breast height), branch height, crown width, branch angle and stem straightness at age 12 were 9.96 m, 14.50 cm, 1.04 m, 6.80 m, $18.82^{\circ}$ and 2.58, respectively. Families of 075 and 052 showed superior height growth and 0511 and 0517 were inferior ones. For DBH growth, 075 and 0413 were best families and 0725 and 0511 were inferior families. Pearson's product moment and Spearman's rank correlation coefficients were all positive for all growth traits except branch angle at ages 10 and 12. This result showed that the families with good height and DBH growth were also superior in stem straightness. In ANOVA, there was a highly significant difference among families in height, DBH, cylindric volume and stem straightness. Branch height, crown width and branch angle were also significantly different among families. Family heritability was higher than individual heritability at ages 10 and 12. Height, DBH and stem straightness were under strong genetic control, showing high family heritability. This implies that high genetic gain could be expected by family selection. Expected genetic gain for each trait was estimated based on the family selection. The highest genetic gain was expected for the traits of branch angle, height and DBH because of the large phenotypic standard deviation and the high family heritability. The growth performance and branch characteristics were weighted by the magnitude of genetic variation and heritability. The weighted values were then subjected to estimate family breeding values. This family breeding value would be applied as a criterion in the genetic thinning of the seed orchard.

• Journal of Korea Foresty Energy
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• v.25 no.1
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• pp.31-38
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• 2006

Quercus mongolica is the most common hardwood species distributed in Korea. This study was conducted to investigate the biomass and energy content of the belowground biomass of Q. mongolica and to obtain the regression equation for estimating root biomass using the tree height and diameter at breast height (DBH). A total of 18 sample trees ranging 20 to 60 year-old were selected in the study sites. Tree height, DBH, age, and weight of stemwood, sapwood, heartwood, stembark, branch, leaf, and root were measured for total biomass. The highly positive correlation was shown between the biomass of most of variables of aboveground components and root biomass. The regression equation of the aboveground total biomass was $log\;W_A\;=\;1.469\;+\;0.992\;log\;D^2H\;(R^2 =0.99)$. The regression equation of the belowground biomass was $log\;W_R\;=\;1.527\;+\;0.808\;log\;D^2H\;(R^2\;=\;0.97)$. The mean energy contents of sapwood, heartwood, bark, leaf, and root were 19,594 J/g DW, 19,571 J/g DW, 19,999 J/g DW, 20,664 J/g DW, and 19,273 J/g DW, respectively. The results obtained from this study can be used to estimate biomass and energy content of belowground using easily measurable variables such as DBH and tree height ranging from 20 to 60-year-old Q. mongolica stands.

• Journal of Korean Society of Forest Science
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• v.84 no.4
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• pp.437-446
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• 1995

This study was carried out to estimate the Korean Pine stand structure such as coefficient of variation of mean DBH, number of trees and volume per ha by Weibull distribution for each age class from I to V, based on photo measurement and timber cursing in Kangwon National University Experimental Forests. The results were summarized as follows: 1) Coefficient of variation of mean DBH for each age class from I to V, which was obtained by converting DBH estimated from crown diameter by photo measurement into quadratic mean DBH, was estimated as 28.88%, 24.13%, 23.29%, 20.27%, and 18.79%, respectively. 2) Number of trees per ha of each age class by Weibull distribution was obtained as 2875, 2100, 1875, 800, and 325, respectively. 3) Volume per ha of each age class was estimated as $22.9m^3$, $66.8m^3$, $101.3m^3$, $209.6m^3$, and $266.8m^3$, respectively. 4) Therefore, aerial photographs will be helpful to estimate the stand structure effectively.

• The Korean Journal of Ecology
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• v.28 no.3
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• pp.163-168
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• 2005

This study was carried out to estimate above-ground biomass and inorganic nutrient distribution for a Camellia japonica stand located Mt. Cheon-gwan, Jeonnam province. Regression analysis of biomass for stem, current twig, branch and foliage versus diameter at breast height(DBH) was used to calculate regression equations of the form of logY = a + blogD(Y: component biomass, D: DBH). Total above-ground biomass for a Camellia japonica stand was 115.2 ton/ha(47.9 for main stem, 1.4 for current twig, 53.4 for live and dead branch, 5.6 for current foliage and 6.9 for ${\geq}1$-yr-old foliage). Component biomass was non-linearly correlated with DBH, and the difference in biomass between ${\geq}1$-yr-old and current foliage increased in proportion to DBH. Current foliage and live branch showed higher N, P and K concentrations compared to ${\geq}1$-yr-old foliage and dead branch, respectively. However, Ca concentration of current foliage and live branch was lower than that of ${\geq}1$-yr-old foliage and dead branch, respectively. Total above-ground inorganic nutrient contents(kg/ha) were distributed as follows; K: 366.4. N: 442.7, Ca: 433.3, Mg: 118.4, P: 50.5 and Na: 25.3. The proportions of inorganic nutrient content for live branch were generally the highest in all the inorganic nutrients.

• Journal of Korean Society of Forest Science
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• v.107 no.2
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• pp.184-192
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• 2018

In this study was implemented to develop tree stem weight prediction equation of Larix kaempferi in central region by selecting a standard site, taking into account of diameter and position of the local trees. Fifty five sample trees were selected in total. By utilizing actual data of the sample trees, 11 models were compared and analyzed in order to estimate four different kinds of weights which include fresh weight, ovendry outside bark weight, ovendry inside bark weight and merchantable weight. As to estimate its weight, the study has classified its model according to three parameters: DBH, DBH and height, and volume. The optimal model was chosen by comparing the performance of model using the fit index and standard error of estimate and residual distribution. As a result, the formula utilizing DBH (Variable 1) is $W=a+bD+cD^2$ (3) and its fit index was 90~92%. The formula for DBH and height (Variable 2) is $W=aD^bH^C$ (8) and its fit index was 97~98%. In summation, Variable 2 model showed higher fitness than Variable 1 model. Moreover, fit index of formula for total volume and merchantable volume (W=aV) showed high rate of 98~99%, as well as resulting 7.7-17.5 with SEE and 8.0-10.0 with CV(%) which lead to predominately high fitness in conclusion. This study is expected to provide information on weights for single trees and furthermore, to be used as a basic study for weight of stand unit and biomass estimation equations.

• Journal of Korean Society of Forest Science
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• v.83 no.4
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• pp.480-485
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• 1994

Growth and wood quality characters such as height, DBH, specific gravity, traceried length and width were measured for 16-year-old open-pollinated progenies of 38 selected plus trees of Abies holophylla Max. The results were as follows ; 1) The superior families in growth and wood quality characters were Chonbuk 4(498.2cm) and Kyonggi 9(485.7cm) for height, Kyonggi 12(9.2cm) and 9(9.1cm) for DBH, Kaongbuk 2(0.480) and Kangwon 7(0.473) for specific gravity, Kyonggi 9(2.77mm) and Kangwon 11(2.71mm) for tracheid length and Kyonggi 9(0.039mm), Kangwon 11, 12 and Kyunggi 7(0.036mm) for tracheid width, respectively. 2) There were significant differences among the families in height and specific gravity at 1% and 5% level. 3) There were high significant negative correlations between specific gravity and other characters such as height, DBH, tracheid length and width at 1% level($r=-0.242^{**}{\sim}-0.635^{**}$) 4) The heritabilities were 0.55 for height, 0.25 for DBH, 0.44 for specific gravity, and 0.24 for tracheid width.

• Journal of Korean Society of Forest Science
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• v.104 no.4
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• pp.527-535
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• 2015

With results from previous Korean studies on forest thinning, we conducted a meta-analysis on the effect of thinning on diameter at breast height (DBH) growth and carbon (C) stocks (tree, litter layer, coarse woody debris (CWD), and soils) in Korean forests. Thinning increased the DBH growth and the C stocks in soils by 39.2% and 12.8%, respectively, while it decreased the C stocks in tree by 30.9%. In contrast, thinning had no significant effect on the C stocks in litter layer and CWD. The DBH growth and the C stocks in tree showed significant correlations with thinning intensity and recovery time. The C stocks in litter layer correlated with recovery time while those in CWD and soils did not show significant correlation neither with thinning intensity nor with recovery time. Regression models of the DBH growth and the C stocks in tree were developed to quantify the effect of thinning intensity and recovery time. An integration of the regression model of the tree C stock into forest carbon models is expected to be essential to quantify the effect of thinning on the C stocks in litter layer, CWD, and soils. We also suggested expansion of study species, long-term and frequent monitoring, and investigation on understory vegetation in order to elucidate changes in Korean forests following thinning practices.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.1
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• pp.29-38
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• 2014

Allometric equations for leaf, branch, stem and total above ground biomass of Pinus koraeinsis trees were developed with diameter at breast height(DBH) of trees, which were growing in a pine plantation with the stand density of 410 tree $ha^{-1}$ and the average DBH of $29.1{\pm}5.2$ cm in Mt. Taewha, Gyeonggi. Damage by Acantholyda parki reduced leaf biomass compared to other studies, however, its contribution to total biomass was minimal among parts. Comprehensive analysis revealed that constant in allometric equation for total above ground biomass (logY=a + blogX) was affected by average DBH and stand density, however, constant b was not. At the stand level, biomass for leaf, brach, stem, total above ground biomass were 6.68 Mg $ha^{-1}$, 18.82 Mg $ha^{-1}$, 101.02 Mg $ha^{-1}$, 126.53 Mg $ha^{-1}$, respectively. We developed a Korean pine stand biomass regression, which explained about 98% of variation with DBH and stand density based on comprehensive analysis.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.287-297
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• 2016

This study aims to identify the relationship between climatic factors and stand mean Diameter at Breast Height (DBH) for two major tree species; Pinus densiflora and Quercus mongolica in Andong-dam basin. Forest variables such as age, diameter distribution and number of trees per hectare from the $5^{th}$ and $6^{th}$ National Forest Inventory data were used to develop a DBH estimation model. Climate data were collected from six meteorological observatory station and twelve Automatic Weather System provided by Korea Meteorological Administration to produce interpolated daily average temperature map with Inverse Distance Weighting (IDW) method. Andong-dam basin reflects rugged mountainous terrain, so temperature were adjusted by lapse rate based correction. As a result, predictions of model were consistent with the previous studies; that the rising temperature is negatively related to the growth of Pinus densiflora whereas opposing trend is observed for Quercus mongolica.