• Journal of Korean Society of Forest Science
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• v.94 no.5 s.162
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• pp.313-320
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• 2005

This study was performed in a 38-year-old Mongolian pine (Pinus sylvestris L. var. mongolica Litvin) plantation in northeast China. Data were collected from 5 sample trees with different canopy position ranging in DBH from 14.6 cm to 23.8 cm. Sawn speciments that included the biggest knot were taken from the stem below the living crown. Number and distribution of knots per whorl below the living crown were studied by relative height below living crown (RHBC). A linear model expressed as function of whorl age (AGE), whorl height ($H_k$) and the stem diameter at which the whorl was located ($D_k$) was developed to predict the knot diameter and angle. The number of annual rings in four periods and the width of respective zone alone stem were used as dependant variables to analyze the knot develop phases. In average, the number of years from branch birth to ceased forming rings was 7.8, the branches remained alive for 4.2 years without forming annual rings, and branches were occluded 14.4 years after their death. These results can provide abundance branch and knot information so as to describe current and past tree growth dynamic of Mongolian pine plantation.

• Journal of Korean Society of Forest Science
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• v.87 no.4
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• pp.611-619
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• 1998

This study was carried out to examine the effects of soil acidification on growth and nutrient status of 2 - year - old Pious densiflora Sieb. et Zucc. seedlings grown for 120 days in brown forest soils acidified with $H_2SO_4$ solution with or without leaching rations from the soil. The concentrations of A1 in the acidified soils increased with increasing amount of $H^+$ added to the soil. The total dry weight of the seedlings was decreased by the addition of the $H_2SO_4$ solution. The increase of Al concentration in the belowground part resulted from the decreased concentration of essential mineral elements such as Ca and Mg in the aboveground part. In addition, a strong positive correlation(r=0.96, p<0.001) was observed between the dry weight of the seedlings and the molar (Ca+Mg+K)/A1 ratio of the soil solution. When the molar (Ca+Mg+K)/Al ratio was approximately 7.0, the dry weight of the seedlings began to decrease compared with that of the seedlings in the control treatment. The seedlings with the molar (Ca+Mg+K)/Al ratio of 1.0 resulted from approximately 40% growth reduction compared with the control value. The results suggest that the molar (Ca+Mg+K)/Al ratio of the soil solution may be a useful indicator for assessing the critical load of acid deposition.

• Korean Journal of Environmental Biology
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• v.29 no.4
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• pp.345-352
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• 2011

We investigated 12 plots using Herles' diversity of structure feature calculation method, which is based on the Shannon-Weaver-Index for estimation of species diversity. This study sought to facilitate a more systematic understanding of the structure of the forest stands in the Korean fir natural forest in Naeseorak. Although the change in the forest structure is dependent on the change in phase, factors of the natural forest were confirmed by associating individual structure features. As shown in the results of diversity of structure features, the diversity of the structure of the fir tree natural forest in Naeseorak was relatively low. The association between species diversity and overall factors (diversity) related with the change in the structure was found to be weak. The association between the number of trees and the diversity of forest structure stands was moderate, showing that the higher the number of trees, the less diverse the forest structure is. In most of the investigated plots, stem volume and volume of dead tree were associated with the height of natural regeneration, but these were not associated with other factors. Height of natural regeneration was found to be correlated to stand density, crown area and crown class, whereas tree height and BHD did not have any association with other factors. Overall, the results of the investigation are helpful in understanding the change in the structure of Korean fir natural forest. Further investigation with more plots is required.

• Journal of Korean Society of Forest Science
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• v.101 no.1
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• pp.62-68
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• 2012

We have investigated needle life span, photosynthetic pigment and nitrogen allocation pattern in the needle of Picea jezoensis in the three populations (Gyebangsan, Deogyusan and Jirisan) to find out growth environmental condition which needs the strategy development of conservation and restoration against population decline. Needle survival rate was the highest in Gyebangsan (87.0%) and the lowest in Jirisan (71.6%), and it decreased with the increase of needle age. Needle chlorophyll a and b in Deogyusan and Jirisan showed higher content in older needle, but chlorophyll content in Gyebangsan was the highest in 2-year-old needle. Carotenoid content was the highest in the needle in Gyebangsan, and it increased along with needle age. Chlorophyll a/b ratio showed the highest value in Jirisan and the lowest value in Gyebangsan. Chlorophyll/carotenoid ratio decreased with needle age, Needle nitrogen content was the highest in Deogyusan (1.51%) and the lowest in Gyebangsan (1.40%), and the older needle had the lower content. In contrast, the highest chlorophyll/nitrogen ratio represented the oldest needle.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.2
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• pp.270-277
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• 2018

Objective: The present experiment has tested the effect of dietary alfalfa flavonoids (AAF) supplementation on the productive performances, carcass characteristics, meat quality and lipid oxidation of growing rabbits. Methods: One hundred and sixty crossbred rabbits (42 days old) were divided into four groups of forty animals each and were fed either a control diet (AAF0) or an AAF0 diet supplemented with 400, 800, or 1,200 mg of AAF/kg per diet (AAF4, AAF8, and AAF12, respectively) from weaning to slaughtering (102 days old). Performance data were recorded over a period of 60 days. At the end of the trial, 12 rabbits were slaughtered per group, and the carcass characteristics were recorded. Moreover, the plasma, liver and dorsal muscles were sampled from 12 rabbits/group, and were analyzed for lipid oxidation. Results: No significant differences were recorded for the performance, carcass characteristics and meat quality traits except for lightness parameter that was lower in the control group. Dietary AAF supplementation significantly (p<0.01) affected the malondialdehyde (MDA) levels of the frozen meat in a dose-related manner, with the lowest value (0.24 mg MDA/kg fresh meat) recorded in the AAF12 group samples. Conclusion: These findings indicated that the dietary inclusion of AAF in rabbit diets improved muscle oxidation stability with no adverse effects on the growth performance of the animals even if a slight impact on meat lightness color parameter was recorded.

• Korean Journal of Medicinal Crop Science
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• v.26 no.6
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• pp.464-470
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• 2018

Background: Ginseng produced by hydroponics can be cultivated without using agricultural chemicals; thus, it can be used as a raw materials for functional foods, medicines, and cosmetics. This study aimed to determine the optimal harvesting time to obtain the highest levels of ginsenoside and ginseng, as this was not previously unknown. Methods and Results: One-year-old organic ginseng seedlings were transplanted and cultivated using hydroponics for 150 days in a venlo-type greenhouse, using ginseng nursery bed soil and a nutrient solution ($NO_3{^-}-N$; 6.165, P; 3.525, K; 5.625, Ca; 4.365, Mg; 5.085, S; $5.31mEq/{\ell}$). Ginsenoside content and fresh and dry weights were higher at 120 days after transplanting than at 30, 60, 90, and 150 days. Total ginsenoside content was 11.86 times higher in the leaf and stem than in the root at 120 days after transplanting. Ginsenosides F1, F2, F3, and F5 were detected in ginseng leaves and stems. These chemical compounds are known to be effective in altering skin properties, including whitening, anti-inflammation, and anti-aging. Conclusions: Optimal harvesting time for ginseng cultivated using hydroponics was 120 days after transplanting when the biomass and ginsenoside content were highest.

• 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.

• The Journal of the Petrological Society of Korea
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• v.24 no.3
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• pp.253-272
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• 2015

The necessity of aggregate resources in Korea has been increased with a rapid economic growth since the 1990s. Construction activities have been increased drastically for last two decades. Such economic activities are much concentrated at big cities in Korea, and recently new neighbouring cities, such as multifunctional administrative city, enterprise city and innocity, are under construction at the surroundings of the cities. This new urbanization asked for an appropriate supply of raw construction materials such as cement, sands and gravels. The aim of this study is to understand and discuss the analysis and prospect of supply and demand of domestic sand and gravel. On the early years, 1990s, about 25% of the total consumption of these sands and gravels comes from riverine deposits; 20% to 25% from marine sands, 40% to 45% from forest rocks and the rest 5% to 15% from old fluvial deposits and crushed rocks. But nowaday the river aggregate, including both sands and gravels of a present river channel and those of the old fluviatile system are decreasing, while the crushed and forest aggregates and marine sand are now the main source of infrastructure resources. Thus it is increasingly necessary to investigate the forest and crushed aggregate resources potential in Korea where a current analysis indicate that the supply of riverine aggregates gradually decreases.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.2
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• pp.12-19
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• 2010

This study was carried out to explore the availability of seedling pots made from paper mill sludge using red pepper species called Nokkwang. The seedling pots were made by several conditions such as different mixing ratios between sludge and old newspaper (ONP), sterilizing treatment and latex coating. After 30 day cultivation in a green house, the growth condition of the red peppers was evaluated by comparison with those raised in the plastics seedling pots. The red peppers in the plastics pot showed a better growth than those in the sludge pots. Sterilizing treatment, latex coating and different mixing ratios between paper sludges and ONP did rarely affect a growth rate of the plant and the contents of inorganic elements. However, latex coating contributed to protection of physical structure of the sludge pots in spite of constant water feeding. Even though some inorganic elements from the sludge pots migrated into the bed soils, electronic conductivity of the bed soils was within the proper range for the plant growth. Finally it was confirmed that the seedling pots made from paper mill sludges could be used to cultivate horticultural plants as the alternative to the plastics pots.

• Journal of Forest and Environmental Science
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• v.29 no.4
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• pp.282-291
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• 2013

Rapid loss in viability of neem (Azadirachta indica A. Juss.) seed is a major problem. Present effort was undertaken for developing a set pattern for assessing of viability and vigour in seed of various mother tree age of neem (Age I-06 years, Age II-15 years, Age III-25 years and Age IV->30 years old). Various viability test viz. triphenyle tetrazolium chloride test, electrical conductivity, excised embryo test, and germination test have been performed on seeds obtained from mother tree age classes. Inconsistency was observed with the TTC and EC test in germination of seed in laboratory as well as nursery. While various vigour tests viz. cold test, chemical stress test (methanol stress test), and accelerated ageing test alongwith ageing index, germination test (G%, MGT and GV) and various seedling growth parameters like seedling length (cm), number of leaves, collar diameter (cm), total biomass (g) alongwith mathematical indices i.e. vigour index, sturdiness quotient, volume index, quality index, root shoot ratio in nursery as well have been taken for study and showed better consistency. On the basis present study results of various viability and vigour test indicated that mother tree age class II performed better in comparison to others and it can be recommended for seed collection. Further it is also recommended that viability of neem seed may be assessed using various laboratory tests like excise embryo test and germination test (G%, MGT and GV) and vigour test may be taken preferably by cold germination test, chemical (methanol) stress test, accelerated ageing test in laboratory and germination alongwith various seedling growth parameters seedling length (cm), number of leaves, collar diameter (cm), total biomass (g) alongwith mathematical indices like Vigour Index, Sturdiness quotient, Volume Index, Quality index, root shoot ratio in nursery as discussed in this study.