• Journal of the Korea Furniture Society
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• v.18 no.2
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• pp.138-142
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• 2007

Optical microscope was used to observe the difference of safranine penetration in Pinus densiflora, Pinus rigida, Pinus koraiensis and Larix kaempferi grown in Korea. It was found that Pinus koraiensis contained the highest number of ray parenchyma and ray tracheids. In longitudinal direction, latewood penetration was found higher than that of earlywood. The number of resin canals was found highest in Pinus koraiensis and lowest in Pinus rigida. The resin canal conducted safranine higher than longitudinal tracheids. In longitudinal direction, safranine diffused from longitudinal tracheid to ray parenchyma through the cross-field pits and from the longitudinal resin canal to ray parenchyma or longitudinal tracheid. Safranine diffused from longitudinal tracheid to its neighboring tracheid through bordered pit or ray parenchyma through the cross-field pits.

• Journal of Forest and Environmental Science
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• v.34 no.3
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• pp.258-261
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• 2018

Drought alters soil microorganisms; however, it is still not clear how soil microbes respond to severe drought conditions. In this study, the responses of soil bacterial community to experimental drought in a coniferous stand were examined. Six $6m{\times}6m$ plots with three replicates of control and drought treatments were delimited. PCR amplification and Illumina sequencing were conducted for cluster analysis of soil bacterial community and species richness and species diversity was analyzed. Along the 393 days of simulated drought from July 2016 to October 2017, soil bacterial species diversity slightly increased whereas species richness decreased in both control and roof plots. Moreover, soil bacterial species richness more decreased in roof plots than in controls. Combining these results, soil bacterial activity might have been altered by simulated drought.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2019.08a
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• pp.149-149
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• 2019

• Journal of Korean Society of Forest Science
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• v.109 no.1
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• pp.72-80
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• 2020

Two strategies for calculating economic feasibility are the machine rate and cash-flow methods. This study used the cash-flow method to evaluate the economic feasibility of the HAM300 yarding operation for extracting tree length logs in Larix kaempferi forest stands. In financial analysis based on 7-year cash-flow, the net present value and pay-back period method were used. We analyzed two scenarios: operating opportunities (50, 100, 150, and 200 days per year) and productivity change yield (7.5 and 10.5 ㎥/scheduled machine hour: SMH). The analysis indicated that high rates of return on extraction activity investment can be achieved when machines are used for >150 days per year. In addition, improved productivity (10.5 ㎥/SMH) increased financial feasibility compared to current productivity (7.5 ㎥/SMH) when machines were operated for 100 days per year. These results suggest that the appropriateness of HAM300 harvesting depends on the number of annual operating days and productivity.

• Journal of Korean Society of Forest Science
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• v.106 no.2
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• pp.169-185
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• 2017

The result of forest vegetation classification could be quite different and dependant on analysis methods. The purpose of this study was to compare the analyzed results for three kinds of methods (physiognomy dominant species, floristic composition and interspecific association) related to vegetation classification. Vegetation data were collected by the 80 quadrates in Mt. Oseo, Chungcheongnam-do from September to October in 2016. We carried out community type classification using above three methods. As a result, the vegetation according to physiognomy dominant species was classified into ten communities such as Pinus densiflora community, Quercus mongolica community, Zelkova serrata community, Quercus acutissima community, Cornus controversa community, Quercus serrata community, Larix kaempferi community, Pinus rigida community, Castanea crenata community and Liriodendron tulipifera community. The vegetation according to floristic composition was classified into 4 vegetation units. It was totally represented by Lindera erythrocarpa community group. And L. erythrocarpa community group was classified into the Rhododendron mucronulatum community (subdivided R. mucronulatum typical group and Styrax obassia group) and Zelkova serrata community (subdivided Larix kaempferi group and Pseudostellaria palibiniana group). As a result of interspecific association, forest vegetation was divided into two groups. And it was considered that the vegetation type by floristic composition and interspecific association significant could be affected by topography. There were lots of vegetation groups or units in the order like 10 types of communities by the physiognomy dominant species, 8 species group and 4 vegetation types by the floristic composition, and 2 types by the interspecific association. In conclusion, vegetation classification methods elicited diverse vegetation groups or units with lots of correlations of environmental factors.

• Korean Journal of Agricultural Science
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• v.38 no.4
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• pp.619-624
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• 2011

The calorific value is the most significant factor in woody biomass utilization. We measured the calorific value by the wood parts (debarked parts and bark) and moisture content for 3 major tree species (Larix kaempferi, Pinus koraiensis, and Pinus rigida). Results showed that the calorific value decreased exponentially as the moisture content increased regardless of tree species and the wood parts. The bark had higher calorific values than woody parts (de-barked parts). In addition, Pinus koraiensis had the highest calorific values among 3 study species.

• Journal of Korean Society of Forest Science
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• v.113 no.3
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• pp.372-381
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• 2024

This study was performed to analyze adequate stand density management criteria for commercial forests of the major coniferous species, Pinus densiflora, P. koraiensis, and Larix kaempferi in South Korea. Relative density (RD) was applied to analyze occurrence of mortality, mean DBH growth, and height-diameter (HD) ratio. The results showed that when RD was 0.7 or higher, the average number of mortality in all three species increased to 15-24 trees/ha, with mortality rates ranging from 20.0%-35.4%. As RD increased, mean DBH growth decreased 0.2-0.5 cm/year by species, but the HD ratio increased 46.9%-71.4%. Consequently, if adequate stand density management criteria are selected with RD 0.7 for P. densiflora and L. kaempferi and RD 0.8 for P. koraiensis, it is considered to increase high-quality timber production with lower mortality and increased growth.

• Journal of Korean Society of Forest Science
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• v.112 no.4
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• pp.502-514
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• 2023

This study was conducted to understand the long-term changes in soil physiochemical properties and seedling growth in Larix kaempferi (larch) stands planted in clear-cut larch and Pinus rigida (pine) forest soils over an 11-year period after reforestation. Two-year-old bare-root larch seedlings were planted in 2009-2010 at a density of 3,000 seedlings ha^-1 in clear-cut areas that harvested larch (Chuncheon and Gimcheon) and pine (Wonju and Gapyeong) stands. We analyzed the physiochemical properties of the mineral soils sampled at 0-20 cm soil depths in the planting year, and the 3^rd, 7^thand 11^th years after planting, and we measured seedling height and root collar diameter in those years. We found significant differences in soil silt and clay content, total carbon and nitrogen concentration, available phosphorus, and cation exchangeable capacity between the two stands; however, seedling growth did not differ. The mineral soil was more fertile in Gimcheon than in the other plantations, while early seedling growth was greatest in Gapyeong. The seedling height and diameter at 11 years after planting were largest in Wonju (1,028 tree ha^-1) and Chuncheon (1,359 tree ha^-1) due to decreases in stand density after tending the young trees. The soil properties in all plantations were similar 11 years after larch planting. In particular, the high sand content and high available phosphorus levels (caused by soil disturbance during clear-cutting and planting) showed marked decreases, potentially due to soil organic matter input and nutrient uptake, respectively. Thus, early reforestation after clear-cutting could limit nutrient leaching and contribute to soil stabilization. These results provide useful information for nutrient management of larch plantations.

• Korean Chemical Engineering Research
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• v.51 no.6
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• pp.739-744
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• 2013

In this study, torrefaction was performed to improve fuel properties of Larch. The optimal condition for torrefaction was investigated by response surface methodology. The torrefaction temperature and time ranged $220{\sim}280^{\circ}C$ and 20~80 min, respectively. As the torrefaction temperature and time increased, the carbon content of torrefied biomass increased from 49.36 to 56.65%, while its hydrogen and oxygen contents decreased from 5.56 to 5.48% and from 37.62 to 31.67%, respectively. The weight loss and calorific value increased with SF, while energy yield decreased. At the severe torrefaction condition (SF 7), the weight loss and calorific value were 26.58% and 22.30 MJ/kg, respectively. The energy contained in torrefied biomass increased to 20.41%, when compared with the untreated biomass. As the torrefaction severity increased, the energy yield decreased due to the relatively high weight loss of biomass. Therefore, the highest energy yield was obtained at high calorific value and low weight loss of biomass (SF 5.72).

• Journal of the Korean Wood Science and Technology
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• v.40 no.2
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• pp.133-140
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• 2012

The antifungal activities of the essential oils from Pinus densiflora, Pinus koraiensis, Abies holophylla, Larix kaempferi, Cryptomeria japonica and Chamaecyparis obtusa against Aspergillus fumigatus were evaluated. Essential oils were extracted from each conifer leaves for 8 h using water distillation method. The essential oil from A. holophylla appeared the strongest antifungal activity among the six oils with MIC value 0.125 mg/$m{\ell}$. The composition of the A. holophylla oil was analysed by GC/MS and then MIC was determined for main constituents of the oil. As the results, borneol and ${\alpha}$-bisabolol, which have a hydroxyl group, showed effective antifungal activities against A. fumigatus (0.25 mg/$m{\ell}$). In addition, the synergistic antifungal effects were observed in the combination of borneol and ${\alpha}$-bisabolol.