• Journal of Korean Society of Forest Science
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• v.111 no.1
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• pp.150-164
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• 2022

This study was conducted to provide basic information for the development of silvicultural guidelines and manuals. This was achieved through analysis of tree and stand characteristics according to the first and second thinning in Korean white pine plantations. Data were collected from permanent plots installed at Korean white pine plantations according to thinning intensity, and residual tree and stand variables, including diameter at breast height (DBH), volume, and mortality at age 19-43, were analyzed using data repeatedly collected in 4-5 measurements by experiments. According to one-way variance of analysis, tree DBH and volume were significantly different according to thinning intensity (p<0.05). DBH distribution was skewed to the left side over time as thinning intensity was heavier. Thus, tree DBH values were larger in heavy thinning plots with increased age. The periodic annual increment (PAI) of DBH was higher with heavier thinning intensity and fewer years after thinning. The PAI range by thinning intensity was 0.48-0.95 cm/year at age 19-24. In addition, the PAI increased in heavy thinning plots after the second thinning; The PAI range by thinning intensity was 0.29-0.67 cm/year after the second thinning at age 37-42. The PAI of tree volume differed according to thinning intensity, and the PAI value did not decrease obviously, in contrast to the pattern of the DBH PAI. Stand volume was generally higher in high-density stands, and the PAI of stand volume was high in unthinned and light thinning plots. Mortality was highest in unthinned plots, and the differences in mortality according to thinning intensity increased over time. Consequently, the growth of DBH and tree volume was lower as stand density increased, but this growth was facilitated with appropriate first and second thinning operations.

• Journal of agriculture & life science
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• v.43 no.6
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• pp.1-6
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• 2009

The purpose of this study was to analyze annual tree ring growth characteristics for major tree species distributed in Chungbuk province. A total of 800 sample trees from 56 permanent sampling plots measured by the 5th Korean National Forest Inventory Program in 2007 was used for the calculation of annual growth rates. According to the results of this study, the species of Robinia pseudoacacia(2.30mm/yr) showed the best annual tree ring growth rates and the others are Quercus serrata(2.27mm/yr)>Prunus sargentii(1.98mm/yr)> and Larix leptolepis(1.98mm/yr) in order. Most of the major tree species in Chungbuk province, as tree age and stand density increased, annual tree ring growth rates tended to decreased. This information could be very useful for forest managers to understand annual tree ring growth characteristics in Chungbuk province.

• 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.104 no.4
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• pp.536-542
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• 2015

This study was examined for the growth response of tree diameter and volume to thinning treatments from different thinning intensities using three long-term thinning trials for Japanese Evergreen Oak (Quercus acuta Thunb.) stands in Wando island, Korea. After thinning in 1999, annual tree growth of diameter and volume was highest in heavy thinned stands for individual tree and this growth pattern of thinning response showed similar tendency to the individual tree growth response in light thinned stands. By increasing diameter growth, the value of H/D ratio (HDR) as an indicator of stem form was properly decreased and improved up to 80%. Although there is significant growth response of basal area in both heavily and lightly thinned stands, the growth potential both of heavily and lightly thinned stands in total stand volume is not likely to reach at the level of unthinned stands because of basal area growth loss associated with both light and heavy thinnings.

• Proceedings of the Korean Institute of Landscape Architecture Conference
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• 2003.03a
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• pp.113-115
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• 2003

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.258-265
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• 2009

This research was conducted to compare drymatter production and yield pattern between commercial glasshouse (G) and plastic greenhouse (PG) in Korea. In both greenhouses sawing and plating of sweet pepper was 28 August and 27 September, 2007. Destructive measurement and yield of sweet pepper, cv. 'Derby', was obtained from January to May, 2008. Averaged light transmissivity over 20 times observed 65% in G and 51 % in PG. The averaged daily radiation sum of greenhouses during whole growing period was $9.03MJ/m^2/day$ for G and $7.37MJ/m^2/day$ for PG Leaf area index (LAI) in G crop was 36% higher than the crop in PG at the end of experiment (247days after planting: DAP), whereas there was no significantly difference for 212 DAP in both greenhouses. Total dry matter production was $1759.9g{\cdot}m^{-2}$ for G and $1308.5g{\cdot}m^{-2}$ for PG Fruit production observed $14.1kg{\cdot}m^{-2}$ in G and $7.8kg{\cdot}m^{-2}$ in PG. There was slightly difference measurement of dry matter distribution of generative or vegetative parts to total dry matter between G and PG.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.3
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• pp.1-12
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• 2018

This study was conducted to obtain a reliable result assessing proper amount of solid swine manure for the growth of Deutzia crenata seedlings. Seedling growth dry weight, chlorophyll content inorganic nutrients and soil chemical properties were investigated. 1. When treated with solid swine manure, seed germination rate was highest on the control. However, germination rates tended to decrease when treated with swine manure at high concentrations. 2. The growth of seedlings treated with swine manure was always higher than that of in control. At the 1.0% of swine manure treatment, the growth rate of the seedlings was highest. 3. Seedling dry weight was highest at the 1.0% swine manure treatment. The amount of inorganic nutrients absorbed by the seedling was generally high with the 1.0% treatment, declined sharply with the 2.0% treatment. 4. For the planting soil of Deutzia crenata, the higher the concentration of swine manure, the lower the soil pH. However, nitrogen, available P, K, Na, Mg and Ca contents in the soil have increased with higher concentrations.

• Journal of Korea Foresty Energy
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• v.20 no.2
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• pp.46-57
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• 2001

This study was conducted to provide tending operation information for the effective management in unmanaged artificial forests of Pinus densiflora for. erecta, Pinus rigida, and larix leptolepis, based on the study of the comparison of tree growth pattern by residual stand density after thinning practices. Followings are summarized results of this study. 1. The diameter growth of residual trees was increased as residual stand density decreased by thinning practices in the stands of Pinus densiflora for. erecta, and Pinus rigida, and subcompartment (Ga) and (Na) of Larix leptolepis. The statistical analysis noted that the tree growth was significantly different by the residual stand density. 2. The height growth did not show corresponding results by stand density treatment pattern, which indicated that the height growth was not directly influenced by residual stand density, but by site quality of the stand. 3. The diameter increment for the last six years was proportionately increased in larger diameter classes and less dense stands.

• Journal of Life Science
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• v.14 no.4
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• pp.560-566
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• 2004

Agrocybe aegerita is Hymenomycetes fungus belonging to the order Agaricales and family of Bolbitiaceae. Much less is known about liquid culture of Agrocybe aegerita. Thus, the present study was to investigate the liquid cultural characteristics of Agrocybe aegerita my-celium. The optimal medium for the mycelial growth and density was ME medium, optimal tem-perature and initial pH were 25$\pm$1$^{\circ}C$ and 5.5, respectively. And optimal culture time for mycelial growth was 12 days. The modified optimal medium compositions were dextrin 3% (w/v), yeast extract 2% (w/w), MgSO$_4$0.05% (w/v), and KH$_2$PO$_4$0.15% (w/v). Under optimal culture conditions, the mycelial growth of modified optimal medium was higher than that of ME medium.

• Korean Journal of Environment and Ecology
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• v.20 no.4
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• pp.425-435
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• 2006

The objectives of this research were to investigate the drought resistance as well as the growth of Wisteria floribunda seedlings with the soil water conditions. The seedlings for the research were grown in pots with strict water content control on a frame located outdoors. During the experiments, the soil water contents were adjusted to 5, 10, 20, 30, 40, 50, 60, and 70%. In addition, the effects of Rhizobium inoculation on the growth of seedlings were investigated. The experimental results are summarized as follows: 1. The seedlings in the pots with 5% soil water content withered to death due to the water stress. Withering or any distinct growth was not observed from the seedlings in the 10% soil water content. It can be inferred from these results that about 5% of soil water content is the wilting point of W. floribunda seedlings and about 10% is the critical soil water content of its growth in this experiment soils. Therefore, it seems that W. floribunda possesses a good drought resistance. 2. From the analyses of the main growth parameters such as stem elongation, diameter growth, leaf area growth and total dry weight, it was found that the seedling growth can be improved with increasing soil water contents. The relation between each growth parameter(Y) and the soil water contents(W) was well described by a quadratic equation, $Y=a+bW+cW^2$. 3. In soil water contents higher than 20%, the seedling growth(Y) was remarkable along with-its extended growing period, and related to the growing period(D) by a quadratic equation, $Y=a+bD+cD^2$. 4. The artificial inoculation of Rhizobiun promoted the growth of Wisteria floribunda seedlings. 5. Rhizobium was found to be more readily inoculated and to form more root nodules compared to seedlings grown in higher soil water contents.