• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.2
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• pp.1-9
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• 2009

Due to the increase of carbon dioxide in the atmosphere and global warming, the importance of forest ecosystems, as a place of carbon accumulation and emission, has received a great amount of recognition lately. This study was performed to help understand and provide the current status of carbon cycle in the pinus densiflora stand, Korea. The samples were collected from average 35-years-old Pinus densifiora rands in Gongju, Youngdong, Chungsan, Muju, Mupung, and Jangsu regions. Total thirty aboveground sample trees were cut, and ten roots were sampled, and soil samples were collected. Average carbon concentrations in foliage, branch, stem bark, stem wood, and root were 55.7%, 56.0%, 56.0%, 57.3%, and 56.5%, respectively. Carbon content was estimated by the model $Wt=aD^b$ where Wt is oven-dry weight in kg and D is DBH in cm. Total carbon content (aboveground and root) was 42.39tonC/ha in the Pinus densiflora stand. The proportion of each tree component to total carbon content was high in order of stemwood, root, branch, stem bark, and foliage. Total net primary production (aboveground and root) was estimated at 6.51tonC/ha/yr in Pinus densiflora stand. The proportion of each tree component to total net primary carbon content was high in order of sternwood, root, branch, foliage and stembark. Soil carbon contents in the study sites was 43.51tonC/ha at 0-50cm soil depth.

• Journal of the Korean Wood Science and Technology
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• v.32 no.4
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• pp.66-73
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• 2004

Three species of Italian poplar (Populus euramericana), red pine (Pinus densiflora) and oriental oak (Quercus variabilis) were selected for this study. They were cut so that the distances between each of tips and roots for a pair of fingers were 0, 0.15, 0.30 and 0.45 mm. Poly vinyl acetate (PVAc) and resorcinol-phenol resin (RPR) were used for finger-jointing. Compressive test parallel to the grain was conducted for the finger-jointed specimens. The results were as follows: The efficiency of compressive Young's modulus of finger-jointed timber to solid wood indicated low values, whereas the efficiency of compressive strength indicated high values of more than 90% in all species, especially, it was found that those of red pine indicated markedly high values of more than 97%. The efficiency of compressive displacement of Italian poplar finger-jointed timber was 2 times higher than solid wood, and it was 1.2 and 1.3 times higher than solid woods in red pine and oriental oak, respectively. Also, it was found that 0, the distance between each tip and root for the fingers, indicated the highest efficiency of compressive strength performance in Italian poplar finger-jointed timber, and for red pine and oriental oak finger-jointed timbers, the distances of 0.15 and 0.30 were found to indicate the highest efficiency.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.11 no.4
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• pp.119-128
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• 2008

In this study, we attempted to seek out the ways to recycle fresh root-chips in the slope revegetation works by breaking tree root wastes occurring during the construction works, also to review the applicability of fresh root-chips as the soil media in slope revegetation works. For this purpose, we organized test units in order to investigate on-site applicability of fresh root-chips (broken chips). In order to examine the desirable ration of combining fresh root-chips with the hydroseeding soil media on the cutting slopes, we organized test units depending on the amount of combination. The following is the main experimental results. 1. At first, we analyzed properties of hrdro-seeding soil media and soil of the experimental sites. The overall results demonstrate that all the test units show proper range for vegetation. 2. We believe that the physical properties of soils in the earlier phase of restoration works on the sloped sites are not greatly affected by the fact whether broken chips exist or not. However, as time elapses, broken chips needs to be investigated further on what kind of impact they have on the soil condition. 3. More species are found in the test unit combining broken chips and we believe that it will contribute to blossoming of green plants and ecological succession of neighboring plants. 4. We performed experiment on possibility for fresh root-chips as substitutes for the hydro-seeding soil-media. In the test unit that combines fresh root-chips, its mixture ratio tends to exceed that of the test unit that does not combine fresh root-chips by 5 %. In case of the Thick-Layer-Soil-Media Hydroseeding works, the mixture ratio of the test unit that combines fresh root-chips after 16 weeks exceeds that of the test unit that does not combine fresh root-chips by 75%. 5. From the result of our experiment, it is obvious that the ratio of mixture and the number of emerging species are higher for the test unit combining fresh root-chips than the test unit that does not combine them. In other words, we can replace the hydro-seeding-soil-media with some Fresh root-chips without affecting the physical property of soil.

• Journal of the Korean Wood Science and Technology
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• v.45 no.4
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• pp.399-408
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• 2017

Research on the rapid and accurate prediction of physical properties of wood using near-infrared (NIR) spectroscopy has attracted recent attention. In this study, partial least squares analysis was performed between NIR spectra and air-dried specific gravity of five domestic conifer species including larch (Larix kaempferi), Korean pine (Pinus koraiensis), red pine (Pinus densiflora), cedar (Cryptomeria japonica), and cypress (Chamaecyparis obtusa). Fifty different lumbers per species were purchased from the five National Forestry Cooperative Federations of Korea. The air-dried specific gravity of 100 knot- and defect-free specimens of each species was determined by NIR spectroscopy in the range of 680-2500 nm. Spectral data preprocessing including standard normal variate, detrend and forward first derivative (gap size = 8, smoothing = 8) were applied to all the NIR spectra of the specimens. Partial least squares analysis including cross-validation (five groups) was performed with the air-dried specific gravity and NIR spectra. When the performance of the regression model was expressed as $R^2$ (coefficient of determination) and root mean square error of calibration (RMSEC), $R^2$ and RMSEC were 0.63 and 0.027 for larch, 0.68 and 0.033 for Korean pine, 0.62 and 0.033 for red pine, 0.76 and 0.022 for cedar, and 0.79 and 0.027 for cypress, respectively. For the calibration model, which contained all species in this study, the $R^2$ was 0.75 and the RMSEC was 0.37.

• 한국균학회소식:학술대회논문집
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• 2014.10a
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• pp.48-48
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• 2014

Arbuscular Mycorrhizal Fungi(AMF) is widespread symbiont forming mutualistic relationship with plant root in terrestrial forest in ecosystem. They provide improved absorption of nutrient and water, and enhance the resistance against plant pathogen or polluted soil, therefore AM fungi are important for survival and maintaining of individual or community of plant. For last decade, many studies about the functional variation of AM fungi on host plant growth response were showed that different geographic isolates, even same species, have different effect on host plant. However, little was known about functional variation of AM fungal isolates originated single population, which provide important insight about intraspecific diversity of AMF and their role in forest ecosystem. In this study, four AM fungal isolates of Rhizophagus clarus were cultured in vitro using transformed carrot (Daucus carota) root and they showed the difference between isolates in ontogenic characteristics such as spore density and hyphal length. The plant growth response by mycorrhizas were measured also. After 20 weeks from inoculation of these isolates to host plants, dry weight, Root:Shoot ratio, colonization rates and N, P concentration of host plant showed host plant was affected differently by AM fungal isolates. This results suggest that AM fungi have high diversity in their functionality in intraspecific level, even in same population.

• The Korean Journal of Food & Health Convergence
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• v.4 no.3
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• pp.6-11
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• 2018

In the Republic of Belarus as well as in the world acute problem of protecting forests from diseases and pests. The damage caused by root rot is essential, therefore, the problem of forest protection is an urgent task. The biologics has the greatest prospects in according with traditional methods of struggle. Deep method of cultivation of a mushroom Phlebiopsis gigantea with use of nutrient mediums on the basis of ethanol stillage and its components (fugat) is researched. Feasibility of use stillage as raw materials in production of a biological product for the wood protection against root decay is shown. The effect of different additives (sawdust, fodder yeast) on the accumulation of reactive biological product - oidy has been studed It was determined that the deep cultivation using sawdust of the highest accumulation oidy (1.5 $10^6units/ml$). It was also found that the stillage is the best breeding ground for fungus biomass accumulation (7.9 9.8 g / l) versus fugat (6.0 6.6 g / l). On the basis of research work the technological scheme for production of a biological product were developed. Based on the conducted studies, a technological scheme was proposed for obtaining a biological preparation by deep cultivation of the fungus Phlebiopsis gigantea.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.432-438
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• 2010

This study was carried out to understand the effect on soil chemical property, ion contents, and growth of Lonicera japonica by treatment of simulated acid rain and wood vinegar. It was treated total 30 times by one time per 2 weeks during 150 days from June to October dividing to various pH level of simulated acid rain (each pH 5.6, 4.5, 3.5 and 2.5) and the control site (pH 6.3). The wood vinegar diluted with 500 times was also treated total 10 times by one time per 2 weeks at the experimental sites. The soil pH was reduced as pH level of simulated acid rain was decreased. The organic content, total nitrogen, and Av. $P_2O_5$ in soil showed a tendency to increment. However, the soil improvement effect was exposed to be insufficient when a wood vinegar was treated. In the component of the plant body, $SO_4{^2}$ and $NO_3{^-}$ increased due to the simulated acid rain treatment and the increment ratio was reduced in the wood vinegar treatment plot. In addition, the cation contents showed a tendency to variation due to pH of simulated acid rain. And it showed more increment in the leaves than the root. The early fallen leaves and growth inhibition of L. japonica showed up after the simulated acid rain treatment but the growth of L. japonica increased after the wood vinegar treatment.

• Journal of Ecology and Environment
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• v.37 no.4
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• pp.177-184
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• 2014

This study was conducted to develop allometric equations and to determine the stem density and biomass expansion factor (BEF) for the estimation of the aboveground and belowground biomass of Cryptomeria japonica in Jeju Island, Korea. A total of 18 trees were harvested from the 40-year-old C. japonica stands in Hannam experimental forest, Jeju Island. The mean biomass of the C. japonica was $50.4Mg\;ha^{-1}$ in stem wood, $23.1Mg\;ha^{-1}$ in root, $9.6Mg\;ha^{-1}$ in branch, $4.6Mg\;ha^{-1}$ in needle and $4.3Mg\;ha^{-1}$ in stem bark. The diameter at breast height (DBH) was selected as independent variable for the development of allometric equations. To evaluate the performance of these equations, coefficient of determination ($R^2$) and root mean square error (RMSE) were used and results of the evaluation showed that $R^2$ ranged from 71% (root biomass equation) to 96% (aboveground biomass equation) and the RMSE ranged from 0.10 (aboveground biomass equation) to 0.33 (root biomass equation). The mean stem density of C. japonica was $0.37g\;cm^{-3}$ and the mean aboveground BEF was $1.28g\;g^{-1}$. Furthermore, the ratio of the root biomass to aboveground biomass was 0.32.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.11
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• pp.725-732
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• 2014

Phytoremediation is a technology to mitigate the pollutant concentrations such as metals, pesticides, solvents, oils, or others in contaminated water and soils with plants. The plants absorb contaminants through the root and store them in the root, stems, or leaves. Rapid growth trees such as poplar are used to remove low concentrated contaminants eco-friendly and economically in a wide contaminated region. This study was practiced to evaluate an activated carbon production system by using poplar wood discarded after phytoremediation. Life cycle assessment methodology was used to analyze environmental impacts of the system, and the functional unit was one ton of harvested poplar. It was estimated that the small size rotary kiln for activated carbon production from poplar wood had an environmental benefit in optimized conditions to minimize energy consumptions. The results of an avoided environmental impact analysis show that the system contribute to reduce environmental impacts in comparison with activated carbon production from coconut shell.

• Journal of the Korean Wood Science and Technology
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• v.19 no.4
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• pp.43-51
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• 1991

This study was carried out to determine the withdrawal strength of various screws according to root diameter of screw and embeded length on the face and edge of domestic particleboard and medium density fiberboard. The obtained results were as follows: 1. The withdrawal strength of screw in domestic particleboard and medium density fiberboard was closely related to embeded length of the screw but less dependent on root diameter of the screw. 2. The withdrawal strength on the face and edge of domestic particleboard could be predicted by means of the following expression: $F_{Pf}=4.60{\times}D^{0.24}{\times}L^{1.14}(R^2=0.87)$ $F_{Pe}=0.54{\times}D^{0.43}{\times}L^{1.73}(R^2=0.84)$ Where: $F_{Pf}$ : withdrawal strength on the face of particleboard(kgf) $F_{Pe}$=withdrawal strength on the edge of particleboard(kgf) D=diameter of the screw(mm) L=embeded length(mm) 3. The withdrawal strength on the face and edge of domestic medium density fiberboard could he predicted by means of the following expression: $FM_f=1.53{\times}D^{0.53}{\times}L^{1.39}(R^2=0.93)$ $F_{Me}=1.14{\times}D^{0.66}{\times}L^{1.36}(R^2=0.87)$ where: $F_{Mf}$ = withdrawal strength on the face of medium density fiberboard(kgf) $F_{Mf}$=withdrawal strength on the edge of medium density fiberboard(kgf).