• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.3
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• pp.145-151
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• 2006

The purpose of this study was to analyze the relationship between the annual variation in diameter growth of Quercus spp. and climatic factors such as monthly temperature, precipitation and solar radiation in central and northern Korea. Annual diameter growth was measured by using stem cores of 262 Quercus trees, and the correlation between the diameter growth and the climatic factors was analyzed. Mean diameter growth of Quercus spp. in Jungwangsan was larger than that in Woraksan, and mean diameter growth by the species was large in order of Q. serrata>Q. variablis>Q. mongolica>Q. dentata. The diameter growth pattern of Quercus spp. in Woraksan was different from that in Jungwangsan. Positive correlations between diameter growth of Quercus trees and temperature or the solar radiation during July were found in Jungwangsan. Significant correlations between diameter growth and solar radiation during March and precipitation during June were found in Woraksan. It is suggested that climatic factors similarly affect the diameter growth of Quercus spp. in a mountainous terrain, but influences of the climatic factors depend on other environmental conditions such as altitude, topography and soil depth.

• Journal of Forest and Environmental Science
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• v.27 no.2
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• pp.113-118
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• 2011

This study was carried out to analyze annual diameter growth characteristics for major 11 tree species using the data for Gangwon province of the National Forest Resources Inventory in 2007. The annual diameter growth of coniferous species was 5.02 mm, 4.70 mm, and 3.90 mm in Korean white pine, Japanese larch, and Korean red pine, respectively. In growths of the deciduous trees, dogwood, basswood, and cork oak had 3.55 mm, 3.48 mm and 3.01 mm, respectively. Average of the annual diameter growths for all species was 3.38 mm. The relationship between diameter growth and age class showed that the growth rate decreased for all species as age increased. The age class II had the highest annual diameter rate. In relation of the stand density(trees per hectare) and diameter growth, the diameter growth tended to decrease as the stand density increased for most species, especially Korean white pine, cork oak, and basswood. Finally age had the highest value in the correlation coefficients between measurement factor and growth rate regardless of species.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.674-677
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• 2002

Vertically aligned CNTs were grown on Fe-deposited $SiO_2$ substrates using thermal CVD of acetylene gas. The size of Fe particle is controlled by the flow rate of $NH_3$ and pretreatment time, which leads to control the diameter of CNTs. As the diameter of CNTs decreases, the growth rate is enhanced with an inverse dependence of the CNT diameter. The growth rate of CNTs increases linearly as the growth time increases until 30 min but is rapidly decreased over 40 min. We found an inverse relation between the diameter and growth rate of carbon nanotubes. As the diameter of CNTs increases, the compartment layers of bamboo-shaped CNTs appear more frequently. A base-growth model is suitable to explain the dependence of growth rate and structure of CNTs on the diameter size of catalytic particles.

• Journal of Korean Society of Forest Science
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• v.96 no.2
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• pp.160-169
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• 2007

The data used to develop distance-independent individual models for natural mixed forests were collected from 712 remeasured permanent sample plots (25,526 trees) of 10-year periodic from 1990 to 2000 in Baihe Forest Bureau of Changbai Mountains, northeast China. Based on analyzing relationship between diameter increment of individual trees with tree size, competitive status, and site condition, the diameter growth models for individual trees of 15 species growing in mixed-species uneven-aged forest stands, that have simple form, good predicting precision, and easily applicable, were developed using stepwise regression method. The main variables influencing on diameter increment of individual trees were tree size and competition, however, the site conditions were not significantly related with diameter increment. The tree size variables (lnDBH and $DBH^2$) were the most significant and important predictors of diameter growth existing in all 15 growth models. The diameter increment was directly proportional to tree diameter for each species. For the competitive factors in growth model, the relative diameter (RD), canopy closure (P), and the ratio of diameter of subject tree with maximum diameter (DDM) were contributed to the diameter increment at a certain extent. Other measures of stand density, such as basal area of stand (G) and stand density index (SDI), were not significantly influenced on diameter increment. Site factors, such as site index, slope and aspect were not important to diameter increment and excluded in the final models. The total variance explained by the final models of squared diameter increment ($R^2$) for all 15 species ranged from 35% to 72% and these results compared quit closely with those of Wykoff (1990) for mixed conifer stands. Using independent data set, validation measures were evaluated for predicting models of diameter increment developed in this study. The result indicated that the estimated precision was all greater than 94% and the models were suitable to describe diameter increment.

• Journal of Korean Society of Forest Science
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• v.95 no.1
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• pp.131-138
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• 2006

This study was conducted to assess the diameter growth patterns of Quercus mongolica and Quercus variabilis dominant species in natural deciduous forests in Korea. The diameter growth data were collected from 83 destructively sample trees for stem analysis in Gangwon-Do region. The relationship between diameter growth and 14 tree measurements was also analyzed. The average diameter growth rate of dominant trees for both species increased until ages of 15-20 years, and exhibited generally constant trend for subsequent ages. The diameter growth rate of both species ranged from 0.09-0.83 cm/yr across the all ages. Average annual diameter growth for last 5 measurement years was 0.28 cm/yr for Quercus mongolica and 0.27cm/yr for Quercus variabilis. The observed growth rate decreased with decreasing crown class. The difference between diameter growth rates for different crown classes was only statistically significant (p<0.0001) for Quercus mongolica. Pearson correlation coefficient between the diameter growth rate decreased with relative diameter (r=0.64), relative height (r=0.61), exposed crown area (r=0.58) and total crown area (r=0.56) for Quercus mongolica. For Quercus variabilis, Pearson correlation coefficient decreased with dbh (r=0.57), crown width (r=0.55), age (r=0.39), competition index (r=-0.39), and height (r=0.35).

• Journal of People, Plants, and Environment
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• v.24 no.6
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• pp.629-638
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• 2021

Background and objective: This study was conducted to develop diameter growth models for thinned Quercus glauca Thunb. (QGT) stands to inform production goals for treatment and provide the information necessary for the systematic management of this stands. Methods: This study was conducted on QGT stands, of which initial thinning was completed in 2013 to develop a treatment system. To analyze the tree growth and trait response for each thinning treatment, forestry surveys were conducted in 2014 and 2021, and a one-way analysis of variance (ANOVA) was executed. In addition, non-linear least squares regression of the PROC NLIN procedure was used to develop an optimal diameter growth model. Results: Based on growth and trait analyses, the height and height-to-diameter (H/D) ratio were not different according to treatment plot (p > .05). For the diameter of basal height (DBH), the heavy thinning (HT) treatment plot was significantly larger than the control plot (p < .05). As a result of the development of diameter growth models by treatment plot, the mean squared error (MSE) of the Gompertz polymorphic equation (control: 2.2381, light thinning: 0.8478, and heavy thinning: 0.8679) was the lowest in all treatment plots, and the Shapiro-Wilk statistic was found to follow a normal distribution (p > .95), so it was selected as an equation fit for the diameter growth model. Conclusion: The findings of this study provide basic data for the systematic management of Quercus glauca Thunb. stands. It is necessary to construct permanent sample plots (PSP) that consider stand status, location conditions, and climatic environments.

• Korean Journal of Materials Research
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• v.13 no.6
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• pp.404-408
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• 2003

SiC nanorods have been grown on Si (100) substrate directly. Tetramethylsilane and Ni were used for SiC nanorod growth. After 3minute, SiC nanorod had grown by CVD. Growth regions ware divided by two regions with diameter. The First region consisted of thin SiC nanorods having below 10 nm diameter, but second region's diameter was 10∼50 nm. This appearance shows by reduction of growth rate. The effect of temperature and growth time was investigated by scanning electron microscopy. Growth temperature and time affected nanorod's diameter and morphology. With increasing growth time, nanorod's diameter increased because of the deactivation effect. But growth temperatures affected little. By TEM characterization, grown SiC nanorods consisted of the polycrystalline grain.

• Journal of Environmental Science International
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• v.27 no.7
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• pp.555-560
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• 2018

This study conducted to analyze the growth characteristics of old Prunus yedoensis on Jeju island. The diameter growth per year was measured using a DTRS-2000 instrument. The DBH, ground DBH and height of the investigated P. yedoensis were 137 cm, 143 cm, and 15.5 m, respectively. Our analysis showed that the age of the old P. yedoensis was 93 years. An annual diameter growth of $2.85mm{\pm}0.96$ was observed. The result of age estimation, about $265{\pm}64$ years in P. yedoensis on Jeju island. This information could be useful to understand the annual diameter growth characteristics the P. yedoensis distributed on Jeju island.

• Journal of Korean Society of Forest Science
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• v.100 no.1
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• pp.1-7
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• 2011

The objective of this study was to improve the performance of the existing individual-tree/distantindependent stand growth model in predicting the growth of Pinus koraiensis forest stands. The parameters of diameter growth and mortality prediction models were estimated using periodic annual increment (PAI) of permanent plots and the performance of the models were compared with that of the existing ones using mean anuual increment (MAI). The diameter growth model includes crown ratio, potential diameter growth and modifier to compute for competitions of trees of a stand. In deriving the mortality prediction model, the parameters were estimated based on PAI which was also estimated as the function of MAI due to the lacking of permanent plot data. The results of this study showed that the newly-estimated functions based on PAI provide more realistic patterns in diameter growth of individual trees. The new approach using PAI in mortality model seems to overcome the over-estimate problem by the MAI-based model in estimating mortality of stand trees.

• Journal of Korean Society of Forest Science
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• v.77 no.2
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• pp.216-222
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• 1988

This study was conducted to investigate the effect of meteorological factors on the diameter growth and Key-year in Pinus koraiensis and Pinus densiflora trees grown in Chuncheon and Hongcheon. The results obtained were summarized as follows : 1. The diameter growth of Pinus koraiensis was better than that of Pinus densiflora grown in the same meteorological condition and site environment. 2. The influence of meteorological factors on the diameter growth of Pinus koraiensis was the highest in the descending order fog, hours of sunshine, precipitation, relative humidity, warm index, and evaporation. 3. The influence of meteorological factors on the diameter growth of Pinus densiflora was the highest in the descending order fog, hours of sunshine, relative humidity, precipitation, and warm index. But evaporation was not significant. 4. The Key-years for Pinus koraiensis and Pinus densiflora trees appeared in 1964 and 1913 when the diameter growth was influenced by the specific climate change.