• Journal of Korean Society of Forest Science
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• v.35 no.1
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• pp.56-60
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• 1977

This experiment was conducted to determine the responses of some pine species to acidity of cultured soils, and absorption behavior of alkaline elements and to observe the growth characteristics during afforesting period. The results were summarized as follows. 1. Total dry weight indicating growth volume was not much influenced by the acidity of cultured soils (pH 4~8) in all of the 4 species studied. Pinus koraiensis showed more dry weight than any other species, which indicated statistically significant difference. 2. T-R ratio of dry weight was not much affected by the acidity of cultured soils (pH 4~8) and the difference of cultured soils (pH 4~8) and by species. Growth phase also did not show remarkable change through the experiment period. 3. The average sodium content ratio in the plant body had no correlation with cultured soils (pH 4~8), bue significant differences were recognized among species statistically. 4. It was found that sodium content ratio was not much influenced by the cultured soils (pH 4~8), even when the tops and roots were separately analyzed. But, very significant difference was found among the species. Pinus koraiensis especially, showed greater volume growth maintaining low sodium content ratio than any other species, which indicates that Pinus koraiensis has unfavorable characteristics for growing on the seaside.

• Journal of Korean Society of Forest Science
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• v.25 no.1
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• pp.73-79
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• 1975

The Koran native economic and ornamental trees consisting 12 species of 4 gymnosperm families and 3 strains, 6 varieties and 18 species of 12 angiosperm families were irradiated by X-and ${\gamma}$-ray at three different dose rates; 1) acute, 2) semi-acute, and 3) chronic irradiation in order to know their radiosensitivities and the radition effects on mutation induction. Different materials such as seeds, cuttings, scions and plants of the above trees were used in this study, depended upon tree. Most of the materials irradiated showed a high radiosensitivity. The LD-50 of conifer trees ranged from 1.2kR to 13.2kR, averaging 5.4kR which was remarkably higher than field crops. On the other hand the LD-50 dose of hard wood trees ranged from 7.0kR to 18.5kR, averaging 12.7kR. All the tested trees were classified into several categories based upon the relative radiosensitivity of each species which was measured at the dose of LD-50. Variegation was most common among the induced mutants. The other mutations were albino, chlorophyll deficiency, deformed leaf and fruits. It was noticeable that giant-leaf bud-sport mutants were induced in Chinese chestnut (Castanea bungeana) and yellow leaf bud-sport ones appeared in oriental arborvitae (Thuja orientalis).

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.193-193
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• 2011

본 연구에서는 산불발생인자들에 대한 정보를 각각의 요인별로 집적화하고 체계화시킴으로써 산불예방활동의 기초자료로 활용할 뿐만 아니라 산불발생 시, 산불의 거동을 예측하기 위한 자료로 활용하고자 하였다. 발생인자는 크게 연료 및 기상조건 관련 인자와 열적특성 관련 인자로 분류하고 연료 및 기상조건 관련 인자는 수종별, 부위별, 지역별, 고도별, 월별 산림연료들의 구성 요인들에 대해서 분석하였다. 수종별로는 생강나무, 초피나무, 조록싸리, 산초, 개암, 청미래, 고추나무, 철쭉, 조릿대, 털진달래 등 관목류 10개 수종과 김의털, 방아풀, 주름조개풀, 칡, 엉겅퀴 등 초본류 5개 수종 그리고 소나무, 잣나무, 리기다소나무, 해송, 구상나무, 주목 등 6개의 침엽수 및 굴참나무, 떡갈나무, 신갈나무, 갈참나무, 졸참나무, 상수리, 산개벚나무, 고채목, 개서어나무, 굴거리나무, 서어나무, 산벚나무, 때죽나무, 당단풍나무, 단풍나무 등 15개의 활엽수로 구성된 교목류를 대상으로 분석하였다. 부위별로는 생엽, 낙엽, 가지, 수피, 솔방울 등으로 구분하여 분석을 수행했으며, 지역별 구성은 강원(삼척/태백산), 경북(응봉산), 경기(용문산), 충북(월악산), 충남(계룡산), 전북(덕유산), 전남(월출산), 부산(금정산), 제주(한라산) 등 9개 지역을 대상으로 선정하였다. 고도별로는 강원도에 소재하고 있는 태백산을 중심으로 소나무와 신갈나무 생엽을 대상으로 900m, 1000m, 1100m, 1200m, 1300m, 1400m, 1500m 고도를 선정하여 분석을 수행하였다. 월별 분석데이터는 소나무 생엽의 경우, 2008년 6월부터 2010년 11월까지 매월 분석을 수행하였으며, 굴참나무 생엽의 경우에는 2008년부터 2010년까지 매년 6월부터 10월까지 생엽을 채취할 수 있는 기간 동안 분석을 수행하였다. 또한, 열적특성 관련 인자로는 착화특성(무염착화온도, 발염착화시간, 소염시간, 화염지속시간), 발열특성(총열방출량, 평균열방출률), 발연특성(총연기방출량, 최대연기밀도, 최대밀도시간) 등을 고찰하였다. 이와 같은 결과들은 산불발생인자 DB구축으로 부터 산불발생 위험도 및 동태예측의 기본 자료로 활용할 수 있을 뿐만 아니라 지역별 연료별 산림연료의 열적특성 DB로 부터 산불발생시 산불 위험도에 대한 기술정립과 응용성을 향상시킬 수 있을 것으로 사료된다. 이외에도 산림연료 종류별 열적특성을 결과를 토대로 문화재보존지역과 같이 문화적 가치가 높은 시설이나 주유소, 가스 충전소 등의 위험 시설에 대한 효과적인 보호를 위한 대처 방안을 사전에 준비할 수 있어 산불 피해에 대한 국민의 불안감을 줄일 수 있을 것으로 생각된다.

• Journal of Korean Society of Forest Science
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• v.88 no.2
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• pp.169-178
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• 1999

The natural regeneration pattern was evaluated for 11 useful hardwood species in the natural deciduous forest where three different silvicultural practices (two-storied system, shelterwood system, and selection system) were applied and passed by three growing seasons. The study forest was presently dominated by Quercus mongolica in the upper canopy. However, since the analysis indicated that the number of regenerated seedlings of Acer mono and Fraxinus rhynchophylla was fairly abundant enough, these two species were anticipated to have the possibility to be among dominant species along with Quercus mongolica. The results of seedling occurrence after regenerating cutting showed that the number of seedlings was estimated for 3,145/ha(10 times of overstory) in the two-storied system, 6,885/ha(9 times of overstory) in the shelterwood system, and 2,275/ha(4 times of overstory) in the selection system. The estimation was varied by species, and the number of stump sprout was more abundant. The proportion of seedlings was high in 60~80% of overstory density and 60~70% of understory coverage, and high in the site of less than $25^{\circ}$ of slope and from southwest to northwest of aspect. These results were still varied by species. Stump diameter and height had little influence on the occurrence of sprout.

• Journal of Korean Society of Forest Science
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• v.97 no.6
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• pp.597-604
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• 2008

Recognizing the necessity of the development of ecologically sound silvicultural system for the mature Korean pine (Pinus koraiensis), this study was carried out to examine the invasion and growth of understory vegetation after partial cutting. In 1997, the age class VII Korean pine forest in the Experimental Forest of Kangwon National University was opened up about 50% by modified shelterwood cutting with site preparation to induce succeeding regenerations. After 10 years, plenty of hardwood have come to the stand, forming understory vegetation. The abundance and composition of understory vegetation was periodically investigated in the ten $10m{\times}10m$ permanent sample plots, estimating importance values, species diversity index and the distribution of diameter and height of the understory vegetation. Encouraged by canopy opening, the coverage of understory reached perfect closure, composed of 22 tree species and 20 shrub species in 2007. Morus bombycis occupied 29.6% of the total importance value and Cornus controversa was 17.0%, followed by Styrax obassia, Quercus aliena, Quercus mongolica, Acer mono, and Pinus koraiensis. In the year of 2000 the species diversity was highest as 2.547 with 26 tree species and deceasing thereafter, showing 2.220 with 22 tree species in 2007. As understory layer was thickly covered and got grow bigger, some shade intolerant species were disappeared, lowering species diversity. In 2007 the biggest tree was a Quercus aliena with 11.3 cm of DBH and the tallest tree was a Cornus controversa with 9.8m of height. The frequency distribution of number of trees by diameter and height classes formed the inverted-J-shaped curve, supposed to be typical uneven-aged stand.

• Journal of Korean Society of Forest Science
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• v.94 no.1 s.158
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• pp.6-10
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• 2005

This study was conducted to understand the dynamics of naturally regenerated seedlings and saplings in 28years after selective cutting at natural Korean pine-broadleaved forests in Mt. Changbai. The number of naturally regenerated tree species was 16 species in 28 years after selective cutting. The appearance rate of naturally regenerated tree species was 56 percentage and the early-successional tree species of Acer ukurunduense, Acer mono, Acer pseudosieboldianum, Prunus padus var. pubescens, and Maackia amurensis were found in the first 10 years after selective cutting. The seedlings and saplings of shade-tolerant tree species of Pinus koraiensis, Acer mandshuricum, Ulmus laciniata were appeared and the appearance rate was higher than 75% after 15 years while it showed little changes from 19 years after selective cutting. The distribution density of seedlings and saplings of regenerated tree species in selective cutting area was 5,500~6,100 trees per hectare in the first 10 years, and it increased gradually along with the restoration of disturbed area and it could reach 7,500 trees per hectare after 15 years.

• Journal of Korean Society of Forest Science
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• v.110 no.2
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• pp.155-164
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• 2021

Many studies have been conducted on developing automatic plant identification algorithms using machine learning to various plant features, such as leaves and flowers. Unlike other plant characteristics, barks show only little change regardless of the season and are maintained for a long period. Nevertheless, barks show a complex shape with a large variation depending on the environment, and there are insufficient materials that can be utilized to train algorithms. Here, in addition to the previously published bark image dataset, BarkNet v.1.0, images of barks were collected, and a dataset consisting of 53 tree species that can be easily observed in Korea was presented. A convolutional neural network (CNN) was trained and tested on the dataset, and the factors that interfere with the model's performance were identified. For CNN architecture, VGG-16 and 19 were utilized. As a result, VGG-16 achieved 90.41% and VGG-19 achieved 92.62% accuracy. When tested on new tree images that do not exist in the original dataset but belong to the same genus or family, it was confirmed that more than 80% of cases were successfully identified as the same genus or family. Meanwhile, it was found that the model tended to misclassify when there were distracting features in the image, including leaves, mosses, and knots. In these cases, we propose that random cropping and classification by majority votes are valid for improving possible errors in training and inferences.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2013.04a
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• pp.178-178
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• 2013

본 연구는 산림 내 주요 시설물 주변의 소나무, 리기다소나무, 해송, 잣나무, 굴참나무낙엽 5종 및 소나무광솔 등 주요 산불연료에 대하여 연소특성을 분석하고자 착화특성과 전파특성을 실험 한 결과, 발화온도의 경우 소나무낙엽($285^{\circ}C$)이 가장 낮게 측정되어 발화위험성이 가장 높은 것으로 나타났으며, 착화시간의 경우 굴참나무낙엽(발화온도 $305^{\circ}C$)이 3초로 가장 빠르게 나타났고, 화염유지시간의 경우 굴참나무낙엽이 가장 긴 것으로 나타났다. 또한, 전파특성 실험결과 소나무 광솔이 총열방출량 $72MJ/m_2$, 평균열방출율 $40KW/m_2$, 최대열방출량 $206KW/m_2$로 가장 높았으며, 두번째는 소나무낙엽으로 나타났다. 따라서, 실제 산불에서도 소나무광솔과 소나무낙엽이 화염전파에 더 영향을 줄 것으로 사료되었고, 또한, 연료별 탄소배출량 분석 결과 평균$CO_2$방출량이 가장 큰 수종은 리기다소나무낙엽(1.33kg/kg)이며, 평균CO방출량이 가장 큰 수종은 굴참나무 낙엽(0.075kg/kg)으로 나타났다.

• Journal of Korean Society of Forest Science
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• v.86 no.3
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• pp.319-323
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• 1997

Perforated ray cells are identified for the first time in the Korean species of Deutzia glabrata, Deutzia sieboldiana, Hydrangea paniculata, and Philadelphus schrenckii that belong to Hydrangeaceae but not observed in Deutzia gracilis. These ray cells have simple to scalarifrom perforations in Deutzia glabrata which have vessel elements with scalariform perforations, and have scalariform to reticulate perforations in Deutzia sieboldiana, Hydrangea paniculata, and Philadelphus schrenckii which have vessel elements with scalariform perforations. Thus, the perforations of ray cells in Korean Hydrangeaceae appeared not to be exactly the same as the types of scalariform perforation plates in the vessel elements of same wood.

• Korean Journal of Environment and Ecology
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• v.20 no.2
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• pp.94-102
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• 2006

To investigate the forest structure and to suggest basic data of forest in the Dogabsa Valley area of the Weolchulsan National Park, thirty plots, each size is $100m^2$, were set up and surveyed. According to the analysis of classification by TWINSPAN, the community was divided by five groups of Quercus variabilis-Carpinus tschonoskii(I), Pinus densiflora(II), Q. variabilis-P. densiflora(III), Q. variabilis(IV) and Q. aliena-Styrax japonicus community(V). The results of vegetation structure analysis, the forest of Dogabsa Valley area is a transition area of southern part of temperate forest and warm temperate forest zone. The forest is about 40-50-year-old.