• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.285-291
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• 2010

Since 2006, the $5^{th}$ National Forest Inventory (NFI) has been implemented to provide forest resources statistics at the national level and at the county level as well. However, it needs a small-area estimator for estimating forest statistics at the county-level due to a small number of samples collected within a county. This study was conducted to evaluate the applicability of a geographical-based synthetic estimator for estimating forest growing stock volumes at the county level. The NFI-field plots surveyed were post-stratified into three forest cover types. In the synthetic estimator, field plots within a geographical-based super-county for each county were used to estimate stratum weights and stratum mean volumes. It was resulted that estimated stratum weights using the synthetic estimation were significantly differ from forest cover maps. The standard errors of estimated mean by the synthetic estimation that ranged from ${\pm}3.5\;m^3$/ha to ${\pm}7.7\;m^3$/ha were more smaller than those (${\pm}7.8\;m^3/ha{\sim}{\pm}24.7\;m^3/ha$) by the direct estimation. This means that the synthetic estimation is possible to provide more precise estimates of mean volumes.

• Natural Product Sciences
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• v.16 no.4
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• pp.285-290
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• 2010

The inhibition of rat lens aldose reductase (AR) in vitro using methanol extracts from Korean folk plants was investigated. Among them, the extracts of Saussurea grandifolia and Rumex crispus showed highest inhibition of AR. $IC_{50}$ values of the extracts from S. grandifolia and R. crispus were demonstrated 0.07 and 0.05 mg/ml, respectively. Korean folk plants such as S. grandifolia and R. crispus has a possibility of new natural resources for the inhibition of AR.

• 한국약용작물학회:학술대회논문집
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• 2011.09a
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• pp.254-255
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• 2011

• Natural Product Sciences
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• v.18 no.2
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• pp.137-140
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• 2012

The aim of this research was to investigate the industrial application of Zanthoxylum schinifolium. Antibacterial activities of the n-hexane, methylene chloride (MC), ethyl acetate, and butanol fractions of Z. schinifolium were tested against Escherichia coli, Staphylococcus aureus and Helicobacter pylori. Among the fractions, the n-hexane and MC fractions showed the stronger antibacterial activity against H. pylori, with an inhibition zone greater than 10 mm in disc assays. Further testing of bergapten and lupeol from the MC fraction of Z. schinifolium revealed the antibacterial effects against E. coli, S. aureus and H. pylori, suggesting their potential use as antibacterial agents.

• Korean Journal of Agricultural Science
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• v.40 no.1
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• pp.47-51
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• 2013

To search for the aldose reductase (AR) inhibitors from Korean folk plants, the inhibition of rat lens AR in vitro using the methanol (MeOH) extracts from Korean folk plants in Chungcheong Province was investigated. Among Korean folk plants tested, the MeOH extract of Persicaria longiseta showed highest inhibition of AR ($IC_{50}$ value, $5.14{\mu}g/ml$). Consequently, P. longiseta has a possibility of new natural resources for the development of AR inhibitor for the prevention of diabetic complications.

• Journal of Korean Society of Forest Science
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• v.98 no.2
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• pp.133-141
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• 2009

This study was conducted to support for determining an efficient sampling design for forest resources assessments in South Korea with respect to statistical efficiency. For this objective, different systematic sampling designs were simulated and compared based on an artificial forest population that had been built from field sample data and satellite data in Yang-Pyeong County, Korea. Using the k-NN technique, two thematic maps (growing stock and forest cover type per pixel unit) across the test area were generated; field data (n=191) and Landsat ETM+ were used as source data. Four sampling designs (systematic sampling, systematic sampling for post-stratification, systematic cluster sampling, and stratified systematic sampling) were employed as optimum sampling design candidates. In order to compute error variance, the Monte Carlo simulation was used (k=1,000). Then, sampling error and relative efficiency were compared. When the objective of an inventory was to obtain estimations for the entire population, systematic cluster sampling was superior to the other sampling designs. If its objective is to obtain estimations for each sub-population, post-stratification gave a better estimation. In order to successfully perform this procedure, it requires clear definitions of strata of interest per field observation unit for efficient stratification.

• Journal of Korean Society of Forest Science
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• v.103 no.2
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• pp.240-247
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• 2014

This study was conducted as a restoration research in a mountain stream of hydrologic cycle system, which is a type of microsites purposely changing vegetation. The status of vegetation in the three experimental sites, water purification site, small dammed pole site, and aquatic plant restoration site, and one control site within the area of the mountain forest stream were investigated in three different periods, namely before sites restoration, year of sites restoration, and year after sites restoration. After one year of restoration, number of vegetation was increased in the small dammed pool and control site respectively. Vegetation coverage ratio of Zizania latifolia was increased at the water purification area. The effects of habitats restoration appeared to be good a year after the restoration of the experimental sites, in terms of families and species composition of the introduced vegetation, and stream flow. Therefore, the results of the study strongly suggest that fairly effective ways to restore and reproduce degrading mountain hydroecological habitats are by way of forming pool sites and small dams in intermittent mountain streams and re-vegetating with selected plants.

• Journal of Korean Society of Forest Science
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• v.99 no.4
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• pp.590-596
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• 2010

To investigate and to compare the structure of Picea jezoensis forests at Chunwangbong area in the Jirisan National Park, 33 plots(400) were set up by a random sampling method. Dead individuals of Picea jezoensis trees were 15.6%, these were observed mainly in the upper-layer trees. A few seedlings of Picea jezoensis were found in this investigation area. This result indicates that Picea jezoensis might be gradually decreased in the future. Picea jezoensis stands were classified into two major groups by cluster analysis. There were strong positive correlations between Syringa reticulata and Acer pseudosieboldianum, Tripterygium regelii, Quercus serrata; Betula ermani and Lonicera maackii; Euonymus macropterus and Acer ukurunduense; Acer pseudosieboldianum and Tripterygium regelii, and relatively weak negative correlations were showed between Picea jezoensis and Abies koreana; Betula ermani and Acer ukurunduense; Acer pseudosieboldianum and Tripterygium regelii. Species diversity index(H') of investigated groups ranged from 1.0000 to 1.3010.

• Journal of Korean Society of Forest Science
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• v.108 no.1
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• pp.21-28
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• 2019

This study was conducted to determine the carbon (C) and nitrogen (N) response of litterfall components as affected by N addition in compound fertilizer in a Korean red pine (Pinus densiflora S. et Z.) stand in southern Korea. Litterfall in a mature red pine stand was collected for two years following compound fertilizer application ($N_3P_4K_1$; $P_4K_1$) and no fertilization (control). The C concentration of litterfall components was not significantly (P > 0.05) different between the $N_3P_4K_1$ and the control plots, whereas the N concentration of the litterfall components was significantly higher in the $N_3P_4K_1$ plot than in the control plot. The $N_3P_4K_1$ and $P_4K_1$ additions induced a lower C/N ratio of litterfall components compared with the control plot. Annual C and N fluxes via litterfall components were not affected by the $N_3P_4K_1$ addition over the study period, except for reproduction litter. Annual N fluxes via reproduction litter were significantly higher in the $N_3P_4K_1$ plot than in the control plot. Thus, the $N_3P_4K_1$ and $P_4K_1$ additions could modify differently nutrient distribution of the forest floor and mineral soils in a red pine stand. These results indicate that N concentration and C/N ratio in litterfall components are more susceptible to fertilizer application than the C response in litterfall components.

• The Journal of Fisheries Business Administration
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• v.42 no.1
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• pp.37-55
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• 2011

This study is to examine the economic effects of seaweed forest creation project in the case of Jeju Woodo Seokwang－ri. Seaweed forest creation project will raise up the quality and quantity of coastal fisheries resource and improve the structure of coastal ecosystem as a project the recovery of coastal fisheries resource against barren ground like whitening event. The economic effect by seaweed forest creation project can be found not only in the income increase of fishermen but also in reduction of carbon dioxide. The results of this study are summarized as follows: First, the income increase effect of fishermen has economic value of 26,945 thousand won under a 30-year cash flow based on a 8.5% discount rate. This suggests that the seaweed forest creation project increases income of fishermen. Second, the reduction effect of carbon dioxide has economic value of 1,083 thousand won per year. This indicates that the seaweed forest creation project reduces carbon dioxide. In conclusion, the results of this study suggest the seaweed forest creation project has economic value in the case of Jeju Woodo Seokwang-ri.