• 한국산림과학회지
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• 제94권5호통권162호
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• pp.313-320
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• 2005

This study was performed in a 38-year-old Mongolian pine (Pinus sylvestris L. var. mongolica Litvin) plantation in northeast China. Data were collected from 5 sample trees with different canopy position ranging in DBH from 14.6 cm to 23.8 cm. Sawn speciments that included the biggest knot were taken from the stem below the living crown. Number and distribution of knots per whorl below the living crown were studied by relative height below living crown (RHBC). A linear model expressed as function of whorl age (AGE), whorl height ($H_k$) and the stem diameter at which the whorl was located ($D_k$) was developed to predict the knot diameter and angle. The number of annual rings in four periods and the width of respective zone alone stem were used as dependant variables to analyze the knot develop phases. In average, the number of years from branch birth to ceased forming rings was 7.8, the branches remained alive for 4.2 years without forming annual rings, and branches were occluded 14.4 years after their death. These results can provide abundance branch and knot information so as to describe current and past tree growth dynamic of Mongolian pine plantation.

• Journal of the Korean Wood Science and Technology
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• 제51권5호
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• pp.345-357
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• 2023

The present study conducted a stem analysis to trace growth information of Japanese larch (Larix kaempferi) and predict the future changes in growth volume. For this purpose, six L. kaempferi trees over 47 years old were cut at 1-2 m intervals from a height of 0.2 m, and circular plates of 5 cm thickness were collected for stem analysis. The analysis indicated that approximately 1-8 years are required to grow up to chest height. The annual height and diameter growth increased rapidly until the trees are 15 years old and gradually decreased after 20 years. The volume of 30-year-old trees in Oegam-ri forests, which were well-managed after artificial reforestation, was 0.4837 m³, whereas that in unmanaged Singi-ri forests was 0.1956 m³. Although the volume of individual trees differed greatly depending on the forest management status, it was found that the volume increased by 1.67-1.76, 2.49, and 3.49 times at 40, 50, and 60 years age, respectively, compared to the legal harvesting age 30. Therefore, factors such as the carbon dioxide reduction effect, forest management benefits, and the condition of trees at the site should be considered before harvesting trees.

• 한국환경복원기술학회지
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• 제25권3호
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• pp.63-82
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• 2022

The purpose of this study is to compare growth condition of landscape woody plants growing on the different ground structures in apartment complex. I chose Manseok Beach Town Complex 2, in Manseok-dong, Seo-gu, Incheon which has both natural and artificial ground as a subject site. Analysis of three phases of soil showed that artificial ground had average liquid phase of 30.89%, artificial ground mounding 33.88% and natural ground 24.40%. It means that artificial ground has higher water content than natural ground despite having same earthiness. It is believed that artificial ground is not as well drained as natural ground even though it is connected to the natural ground and has a deep soil depth because of mounding. Comparative study between woody plants on natural ground and those on artificial ground demonstrated that trees on natural ground grew 40.4% compared to those on artificial ground(0.875mm more) in terms of diameter growth. Average diameter growth of trees on natural ground was 3.040mm against 2.165mm for those on artificial ground. All 19 tree species which were measured for root diameter growth showed similar or higher growth on natural ground than on artificial ground. When it comes to growth of height, arborvitae showed highest growth on natural ground, followed by Thuja occidentalis, Pinus strobus, Magnolia denudata, Diospyros kaki and Aesculus turbinata. I measured branch growth and rate of leaf adherence of Pinus strobus. Average annual rate of branch growth of woody plants on natural ground was twice as high as those on artificial ground. I could conclude that ground structure influences branch growth of Pinus strobus. Statistics analysis of tree damage demonstrated significant result, meaning that there is a difference in the average damage rate depending on structure of ground. In order to validate growth difference by planting ground, I conducted T-Test of growth of diameter, root diameter, branch and height on woody plants growing on natural and artificial ground. As a result, it is believed that there is a difference in the growth of trees depending on the ground structure. Putting all these results together demonstrates that woody plants on natural ground generally grow better than those on artificial ground, which means ground structure does have an influence on the environment of growth of trees.

• Journal of Forest and Environmental Science
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• 제39권3호
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• pp.119-127
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• 2023

In this study, quantitative models were applied to case parks to estimate the carbon reduction by trees, which was compared and analyzed at the tree and park levels. At the tree level, quantitative models of carbon storage and uptake differed by up to 7.9 times, even for the same species and size. At the park level, the carbon reduction from quantitative models varied by up to 3.7 times for the same park. In other words, carbon reduction by quantitative models exhibited considerable variation at the tree and park levels. These differences are likely due to the use of different growth environment coefficients and annual diameter at breast height growth rates and the overestimation of carbon reduction due to the substitution of the same genus and group model for each tree species. Extending the annual carbon uptake per unit area of the case park to the total park area of Chuncheon a carbon uptake ranging from a minimum of 370.4 t/yr and a maximum of 929.3 t/yr, and the difference can reach up to 558.9 t/yr. This is equivalent to the carbon emissions from the annual household electricity consumption of approximately 2,430 people. These results suggest that the indiscriminate application of quantitative models to estimate carbon reduction in urban trees can lead to significant errors and deviations in estimating carbon storage and uptake in urban greenspaces. The findings of this study can serve as a basis for estimating carbon reduction in urban greening research, projects, and policies.

• Journal of Korean Neurosurgical Society
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• 제62권2호
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• pp.256-262
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• 2019

Objective : Pituitary adenomas (PAs) are often detected as incidental findings. However, the natural history remains unclear. The objective of this study was to evaluate the natural history and growth pattern of untreated PAs. Methods : Between 2003 and 2014, 59 PAs were managed with clinico-radiological follow up for longer than 12 months without any kind of therapeutic intervention. Tumor volumes were calculated at initial and last follow-up visit, and tumor growth during the observation period was determined. Data were analyzed according to clinical and imaging characteristics. Results : The mean initial and last tumor volume and diameter were $1.83{\pm}2.97mL$ and $13.77{\pm}6.45mm$, $2.85{\pm}4.47mL$ and $15.75{\pm}8.08mm$, respectively. The mean annual tumor growth rate was $0.33{\pm}0.68mL/year$ during a mean observation period of $46.8{\pm}32.1months$. Sixteen (27%) PAs showed tumor growth. The initial tumor size (HR, 1.140; 95% confidence interval, 1.003-1.295; p=0.045) was the independent predictive factor that determined the tumor growth. Six patients (11%) of 56 conservatively managed non-symptomatic PAs underwent resection for aggravating visual symptoms with mean interval of 34.5 months from diagnosis. By Cox regression analysis, PAs of last longest diameter over 21.75 mm were a significant prognostic factor for eventual treatment. Conclusion : The initial tumor size of PAs was independently associated with the tumor growth. Six patients (11%) of conservatively managed PAs were likely to be treated eventually. PAs of last follow-up longest diameter over 21.75 mm were a significant prognostic factor for treatment. Further studies with a large series are required to determine treatment strategy.

• 한국산림과학회지
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• 제18권1호
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• pp.9-12
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• 1973

1. 본(本) 조사(調査) 16년생(年生)의 리기다소나무임분(林分)에 대(對)한 재적생장량(材積生長量)과 장래(將來)의 임분재적예측(林分材積豫測) 임분표법(林分表法)에 의하여 추정(推定)한 것이다. 2. 직경성장량(直徑成長量) 조사(調査)는 'Meyer'의 Increment borer법(法)에 의하고 단목재적(單木材積)은 기(旣) 조사(調査)된 V=0.000058 $D^{1.8}{\times}{\cdot}H^{1.1}$의 재적식(材積式)에 의하여 각각(各各) 조사(調査)되었다. 3. 0.33ha의 표준지(標準地)를 설정(設定)하고 표준지내(標準地內) 339본(本)의 임목(林木)에 대(對)하여 95%의 신뢰도(信賴度)로서 조사(調査)한 결과(結果)는 다음과 같다. 1) 직경(直徑)에 대(對)한 직경연년성장량(直徑連年成長量)의 회귀식(回歸式)은 Y=0.1618 +0.0298x. 이다. 2) 2cm 괄약(括約)의 직경분포(直徑分布)에서 전임목(全林木) 본수(本數)의 약(約) 90%가 완전(完全) 1계급(階級) 진급(進級)을 하였다. 3) 임분재적성장율(林分材積成長率)은 16%의 고도(高度)의 성장율(成長率)을 나타냈다. 4) 5개년간(個年間)의 재적성장량(材積成長量)은 46%의 증가율(增加率) 보이고있다.

• 한국산림과학회지
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• 제90권3호
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• pp.363-372
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• 2001

본 연구는 강원도 평창군 가리왕산 및 중왕산 지역 천연 활엽수림내에 분포하고 있는 층층나무의 입지 및 생장 특성을 알아보기 위하여 실시되었다. 이 지역에 출현하는 층층나무림의 지형적 특성은 해발 고도 800m~1,100m에 경사가 급하며, 북동에서 북서방향인 사면-계곡사면이었다. 층층나무가 자라고 있는 토양 특성은 A층의 토양 깊이가 평균 14.3cm로 깊고, 수분함량은 약 37.2%로 높으며, 토양 양료가 비옥한 지역이었다. 또한 층층나무와 함께 상층 임관을 구성하는 주요 수종은 신갈나무, 복장나무, 난티나무, 고로쇠나무 호랑버들 등 이었으며, 층층나무림내 하층 초본류는 십자고사리, 관중, 벌깨덩굴, 큰개별꽃, 곰취, 물봉선, 산괴불주머니, 참나물 등이 출현하였다. 해발고에 따른 층층나무의 생장은 해발고 900m 이하 지역에서 연평균직경생장량이 $4.06({\pm}0.90)mm$, 900m~1,000m 지역에서는 $2.51({\pm}0.65)mm$로 나타났다. 또한 해발고 1,000~1,100m 지역에서는 $3.28({\pm}0.12)mm$, 1,100m 이상 지역에서는 $2.81({\pm}0.35)mm$로 생장이 둔화되었다. 주로 북서사면에서 생장이 좋았으나 지형에 따른 생장량의 차이는 없었다.

• 한국산림과학회지
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• 제94권2호통권159호
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• pp.121-126
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• 2005

This study was carried out to construct a single diameter and a single height model that could localize Chamaecyparis obtusa stand grown in 3 Southern regions of Korea. Dummy variables, which convert qualitative information such as geographical regions into quantitative information by means of a coding scheme (0 or 1), were used to localize growth models. In results, modified form of Gompertz equation, $Y_2={\exp}({\ln}(Y_1){\exp}(-{\beta}(T_2-T_1)+{\gamma}({T_2}^2-{T_1}^2))+({\alpha}+{\alpha}_1Al+{\beta}_1k_1+{\beta}_2k_2)(1-{\exp}(-{\beta}(T_2-T_1)+{\gamma}({T_2}^2-{T_1}^2))$, for diameter and height was successfully disaggregated to provide different projection equation for each of the 3 regions individually. The use of dummy variables on a single equation, therefore, provides potential capabilities for testing the justification of having different models for different sub-populations, where a number of site variables such as altitude, annual rainfall and soil type can be considered as possible variables to explain growth variation across regions.

• 한국산림과학회지
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• 제104권4호
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• pp.536-542
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• 2015

본 연구는 전남 완도 붉가시나무림의 솎아베기 강도 처리에 따른 임분의 생장반응 특성을 비교 분석하였다. 1999년 솎아베기 후 연년 직경 생장량과 연년 재적 생장량에서 강도구의 효과가 가장 큰 것으로 나타났고, 약도구 또한 비슷한 수준의 효과가 있었다. H/D율은 DBH 생장량의 증가로 인해 약 80%까지 임목 형질 개선효과가 나타났다. 솎아베기 이후 강도구와 약도구의 임분 흉고단면적 총 생장량이 증가하는 경향으로 나타났으나, 간벌구의 손실로 말미암아 임분 흉고단면적은 대조구의 생장량 수준까지 장차 회복하기는 어려울 것으로 예측되었다.

• 한국산림과학회지
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• 제96권2호
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• pp.189-196
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• 2007

Allometry, basal area equations, and volume equations were developed with various tree measurement variables for the major species, Quercus mongolica and Quercus variabilis, in Korean natural hardwood forests. For allometry models, the relationships between total height-DBH, crown width-DBH, height to the widest portion of the crown-total height, and height to base of crown-total height were investigated. Multiple regression methods were used to relate annual basal area growth to tree variables of initial size (DBH, total height, crown width) and relative size (relative diameter, relative height) as well as competition measures (competition index, crown class, exposed crown area, percent exposed crown area, live crown ratio). For tree volume equations, the combined-variable and Schumacher models were fitted with DBH, total height and crown width for both species.