• Journal of Forest and Environmental Science
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• v.20 no.1
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• pp.40-50
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• 2004

This study was conducted to provide appropriate tending operation strategies for the natural deciduous forest, by the method of evaluating the stand quality, suggesting the removal plan for the undesirable trees, and predicting improvement cutting practice by tree quality evaluation. The results showed that average number of trees per ha was 717 stems, average DBH was 21.1cm. and average height was 13.6m. Canopy dominant species were in the order of Quercus serrata, Q. variabilis, Q. mongolica, Styrax obassia, and Ulmus davidiana var. japonica. Based on grades of four tree form factors for all tree in the study plots, we estimate the change of tree numbers. DBH and height with the improvement cutting by different tree grade. When the higher tree grade was applied to tending operation, the number of stem was decreased, but the values of DBH and height were not changed much, predicted to improve the stand quality.

• Journal of Wetlands Research
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• v.17 no.3
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• pp.273-282
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• 2015

This study suggested the adaptable plant species according to the change of warmth index (WI) through the Representative Concentration Pathway (RCP) 4.5 & 8.5 climate change scenarios from 2010 to 2099 in Seoul areas. From the scenario analysis results, we expected to change from the cool temperate souther forest zone to the warm temperate forest zone. We found the following adaptable 27 plant species: 6 species in the tree layer, Quercus serrata, Q. variabilis, Pinus densiflora, Q. acutissima, Styrax japonica and P. thunbergii etc.; 7 species in the shrub layer, Ligustrum obtusifolium, Lespedeza maximowiczii, Rhus trichocarpa, Callicarpa japonica, Rubus crataegifolius, Rosa multiflora, and Zanthoxylum piperitum etc.; 3 species in the herb layer, Oplismenus undulatifolius, Pteridium aquilinum var. latiusculum, and Commelina communis ect;, 11 species in the vine plants Smilax china, Cocculus trilobus, Parthenocissus tricuspidata, Lonicera japonica, Paederia scandens, Celastrus orbiculatus, Clematis apiifolia, Rubus parvifolius, Dioscorea batatas, Hydrangea serrata for. acuminata, Zelkova serrata etc.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.488-494
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• 2001

This study was conducted to investigate forest ecosystem assessment which were widely used in Germany and Austria. The study area, Mt. Teawha, is located at Kwangju, Kyunggi-Do province. The methodology of this study considered the following factors. First forest types were classified accoding to species composition and age of tree layer. Naturalness, diversity and rerenees of each forest type were classified into 5 level. Finally, the forest types were assessed by synthesizing those 3 factors. Qurecus mongolica- and valley forest type over 300m was classified as naturalness 4 and Qurecus accustima, Quercus accusitima and Q. variabilis were as naturalness 3. The plantation types on the lower slope showed the level of naturlness 1 or 2. Diversity was similer to naturalness. But indices were different from each other. In the case of Larix leptolepsis plantations, naturalness indicated 1, while diversity showed 3. The valley forest type, wet forest and forest edge were classified into rare forest type. It was concluded that this method could be more efficient method comparing with existing method for assessment of naturality and thereby could contribute for biodiversity conservation in Korea.

• Journal of the Korean Wood Science and Technology
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• v.16 no.2
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• pp.90-97
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• 1988

The rate of utilization of the oak cork (bark of Quercus variabilis Blume) ranges only 40-50%. Therefore, this study was carried out to investigate the chemical properties of the oak cork for increasing the utility. 1) The contents of alkali extractives, organic solvent extractives and ash in the oak cork are similar to those of other barks, but hot and cold water extractives and lignin contents are lower than those of the wood. The carbohydrate (cellulose and hemicellulose) content of the oak cork is similar to that of other barks. The suberin contents in the first and the second bark of the oak cork are 34.8 and 32.2% respectively, in the dry weight. 2) Inorganic component contents of the first bark are similar to those of the second. The pH of the first and the second bark are 3.9 and 4.2%. The caloric values of the first and second bark are 6,263 Kcal/kg, and 5,828 Kcal/kg, respectively, and these caloric values are higher than those of other barks. The sclerencymatous cell content of the first bark which is related to the quality of the oak cork is lower than that of second bark, the contents of the sclerenchymatous cell and lignin show the positive correlation. 3) In the dimension of the cross sectioned cork cell, the first bark is bigger than that of the second. The shape of the cork cell is globular shape in the early bark and discoid shape in the late bark. The cross and the radial section are the same shape, but the tangential section shows difference from the other section.

• Korean Journal of Environment and Ecology
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• v.11 no.2
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• pp.149-159
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• 1997

Eleven plots(10m*10m) were established in Pinus densiflora forests and analized in with TWINSPAN and DCA techniques, to study the comparison of the structure of plant community by soil depth in Ulsan Grand Park. As a result of this analyusis, the communities were divided into two groups : Community B which have shallow one. Community A showed climatic climax which have proceeded from Pinus densiflora to Quercus variabilis, Castanea crenata, Platycarya strobilacea, and at last to Carpinus laxiflora. Community A showed climatic climax which have proceeded fro, Pimus densiflora to Quercus variabilis, Castanea crenata, Platycarya strobilacea, and at last to carpenus laxiflora. Community B showed edaphic climax in sere of Pinus desiflora. The diffrernce of the growth of tree height was showed significantly between two communities. The sample tree aged 30 in Community A was 8.50m high and the sample tree aged 35 in Community B was 3.80m high. Community A was better than Community B in soil characteristics and species diversity indicies.

• Journal of Forest and Environmental Science
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• v.17 no.1
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• pp.62-73
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• 2001

This study was conducted to predict the tractive resistance for tree length logs being skidded by ground based logging machine. The mathematical models for predicting the tractive resistance of tree length log have been developed. The tractive resistance is expressed as a function of log weight, skidding coefficient, and ground gradient. The skidding coefficients for four species of Korean pine, Japanese larch, mongolian oak, and cork oak were determined under laboratory condition using universal testing machine and small soil bin, Three different tractive resistance models were applied to four species and compared with each other. The ratios (T/Wt) of skidding-line tensions to the skidding log weight increased linearly with increment in ground gradient. Semi-ground skidding generally required smaller tensions than ground skidding under given condition. Results of this study can be utilized as basic information for logging machine selection and power requirement of skidding winch.

• Korean Journal of Environment and Ecology
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• v.14 no.4
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• pp.303-310
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• 2001

계룡산국립공원 연애골 계곡부(해발 170-630m)의 해발고와 사면부위에 따른 교목층과 아교목층의 산림구조를 조사하기 위하여 해발고와 사면부위에 따란 48개 조사구를 설정하였다. 계곡 정부를 제외할 때, 해발고가 높아짐에 따라 교목층의 밀도는 증가하는 반면 아교목층의 밀도는 감소하였으며, 교목층과 아교목층 전체의 밀도는 별차이가 없었다. 흉고단면적은 계곡 하부와 중부가 상부에 비하여 높았다. 해발고가 높아짐에 따라 중요치가 증가하는 경향을 보이는 수종은 산길나무, 팥배나무, 쇠물푸레 등이었으며, 감소하는 경향을 보이는 수종은 산벚나무, 졸참나무, 때죽나무, 갈참나무, 밤나무 등이었다. 사면 하부에서 갈수록 중요치가 증가하는 경향을 보이는 수종은 소나무, 신갈나무, 쪽동백나무, 쇠물푸레 드잉었으며, 감소하는 경향을 보이는 수종은 느티나무, 때죽나무, 비목나무, 고로쇠나무 등이었다. 해발고대별 종다양의 범위는 0.971~1.273이었으며, 종다양도와 종수는 계곡 중부가 계곡하부와 상부에 비하여 다소 낮았으나 균재도는 유사하였다. 계곡 정부를 제외한 해발고대간 유사도지수는 30.8~63.7%, 사면부위간 유사도지수는 69.8~79.5%로서 사면부위보다 해발고에 따른 종구성상태의 변화가 더 크게 나타났다. 수종별 중요치에 의한 Cluster 분석 결과 계곡 하부의 사면 상. 중, 하부에 위치한 때죽나무-소나무-낙엽활엽수군집, 계곡 중부의 사면 상, 중, 하부에 위치한 굴참나무-낙엽활엽수군집 계곡 상부의 상. 중. 하부에 위치한 물푸레나무-낙엽활엽수군집, 계곡 정부에 위치한 소나무-신갈나무군집 등 4개 유형군집으로 구분되었다. 종상관을 분석한 결과 느티나무, 물푸레나무, 고로쇠나무, 팽나무, 회나무 등 5개 수종간, 소나무, 쇠물푸레, 산철쭉 등 3개 수종간 유의적인 정의 상관을 보였다. 유의적인 정의 상관을 보인 느티나무, 물푸레나무, 회나무, 사람주나무 등 4개 수종 모두 소나무와 유의적인 부위 상관을 보였으며, 유의적인 정의 상관을 보인 졸참나무는 유의적인 정의 상관을 보인 물푸레나무, 사람주나무, 회나무와, 유의적인 부의 상관을 보였다.

• Journal of Korean Society of Forest Science
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• v.58 no.1
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• pp.60-69
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• 1982

According to the distance from the industrial complex, 5 sample plots were selected to study the changes of vegetational composition of the forest community caused by air pollution in Ulsan. Then 5 subplots were set within a plot. We considered that this gradient analysis by distance could be coincided with the gradual transition of plant succession. Number of species, number of individuals, species diversity, evenness increased and similarity index decreased with increasing distance from the industrial complex. Robinia pseudoacacia, Smilax china appeared to be tolerant to air pollution whereas Quercus variabilis, Q-aliena, Q. dentata and Albizzia julibrissin to be sensitive.

• Journal of the Korean Wood Science and Technology
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• v.35 no.3
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• pp.45-52
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• 2007

The anatomical characteristics of Quercus variabilis woods carbonized at 310 to $350^{\circ}C$ were examined with an optical and scanning electron microscopy, and an X-ray diffraction analysis. Dimensional change and weight loss were also investigated. Volume of wood samples decreased with increasing the carbonization temperature, and checks were developed along with radial direction. Vessel diameter in tangential direction showed higher shrinkage than that in radial direction. Weight loss of samples increased with increasing carbonization temperature. Especially, the weight loss rapidly increased at the temperature ranging from 330 to $340^{\circ}C$. SEM study presented that the cell walls of samples carbonized at below $320^{\circ}C$ showed the layering structure. However, it was revealed that the layering structure was disappeared at $330^{\circ}C$ and over and showed an amorphous-like structure without cell wall layering. Interestingly, the existence of cellulose crystalline substance at $340^{\circ}C$ was confirmed by X-ray diffraction analysis and it was not detected at $350^{\circ}C$. Consequently, it is considered that the critical temperature for carbonization of wood was around $350^{\circ}C$.

• Fire Science and Engineering
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• v.28 no.6
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• pp.22-27
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• 2014

In this study a Fuel bed where surface fire spreads through is made to measure the data such as the flame height, radiation, spread rate and temperature distribution of Fuel bed. As experimental variables species of trees, wind velocities and slop are chosen. Fallen leaves of Quercus Variabilis (Q.V.) and Pinus Densiflora (P.D.) are used as fuel. Wind velocity is controlled by simply designed wind turnnel from 1 to 5 m/s. Slope of fuel bed is changed from $0^{\circ}$ to $30^{\circ}$. For the measurements of temperature distribution and spread rate total 35 of K-type 1.6 mm thermocouples are positioned as a lattice design. Radiant heat flow meters are used besides video camera and thermovision camera.