• Journal of Mushroom
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• v.12 no.3
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• pp.209-215
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• 2014

Changes in physical and chemical properties of oak sawdust were investigated by depth and time for 46 days during the fermentation process of 33 tons of the sawdust for oak mushroom cultivation. The degrees of change in the properties of the sawdust differed depending on the depth and fermentation period. Most of the physical-chemical properties except temperature and pH gradually changed during the fermentation. The temperature change was highly sensitive to the environment at the surface sawdust to 20 cm depth, while it gradually increased to the maximum $58.9^{\circ}C$ at 40~100 cm depths in 12 days and slowly to the maximum at 150 cm depth in 24 days. The moisture content of the sawdust decreased gradually from 31% to 26.5~28.0% in 24 days. Of the chemical properties during the fermentation, pH generally rose from 5.2 to 5.6, but it decreased to 4.4~4.7 at 150 cm depth in 16 days. While the carbon content of the sawdust was 68~70% without significant change, nitrogen content increased from 0.22% to 0.25% and thus C/N ratio gradually lowered from 320 to 280. P content in the sawdust gradually increased from 0.005% to 0.022% for 46 days. Osmotic concentration of the hot water extract of the sawdust varied 41.5~44.2 mmol/kg without significant change by the depth and time. The starch particles within initial ray parenchyma cells of sawdust decreased and fungal hyphae formed on the surface of the sawdust granules and within xylem vessel cells in 35 days. The effect of the sawdust fermentation on oak mushroom cultivation needs continued research.

• Journal of Korean Society of Forest Science
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• v.97 no.1
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• pp.35-44
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• 2008

Mycelial growth of Lentinula edodes on solid or liquid culture media supplemented with differentconcentrations of oak wood vinegar varied depending on the types of wood vinegar or mushroom varieties used.Oak wood vinegar obtained from traditionally carbonizing kiln (TWV) inhibited mycelial growth of L. edodes atthe dilution level of less than $5{\times}10^{-2}$, but stimulated at $10^{-3}$ to $2{\times}10^{-3}$. Wood vinegar from mechanicallycarbonizing kiln (MWV) inhibited at $10^{-3}$, but stimulated at $2{\times}10^{-3}$. In liquid culture media, both wood vinegarinhibited at $5{\times}10^{-2}$, but stimulated at $2{\times}10^{-3}$. Sanjo-302-ho grown in liquid culture media at $2{\times}10^{-3}$, and Sanrim 2and 3-ho grown at $4{\times}10^{-3}$ showed relatively high degree of wood decay (DWD) and growing ability within wood(GAWW) when these isolates were inoculated onto oak wood logs. TWV completely inhibited mycelial growth ofgreen mold fungi, Trichoderma species, tested at $5{\times}10^{-1}$ dilution level, while MWV inhibited at $5{\times}10^{-1}$ to $5{\times}10^{-2}$dilution level. For Diatrype stigma, TWV inhibited mycelial growth at the dilution level of less than $5{\times}10^{-2}$, whileMWV did 80% of mycelial growth at $10^{-2}$, and 100% at $5{\times}10^{-1}$ dilution level. Fresh and dry weight of fruitingbodies harvested after soaking of wood logs into wood vinegar solutions with different concentrations werecompared, and were the highest at $2.5{\times}10^{-2}$ dilution level. Storage test of fruiting bodies at $10^{\circ}C$ for 10 daysshowed that fruiting bodies harvested after soaking in the solution with $2.5{\times}10^{-2}$ dilution level showed the bestfreshness by general test and color changes. In addition, shear force value of L. edodes fruiting bodies measuredby using texture analyzer showed that $2.5{\times}10^{-2}$ dilution level was the best concentration for keeping flesh texture.

• Journal of the Korean Society of Safety
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• v.26 no.5
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• pp.118-129
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• 2011

In this study, species resistant to forest fire were extracted from high trees through an investigation of combustion mechanism. Here, the average flameless ignition temperatures of living leaves, branches and barks of oak were respectively, $365^{\circ}C$, $440^{\circ}C$ and $435^{\circ}C$, and the average flameless ignition temperatures of living leaves, branches, barks and cones of pine tree were respectively, $320^{\circ}C$, $405^{\circ}C$, $435^{\circ}C$ and $363^{\circ}C$. It shows that generally, pine tree has a lower flameless ignition temperature than oak and thus, has a relatively high risk of flameless ignition. When comparing risk of fire depending on ignition characteristics, Quercus serrata had a low risk of stem fire, and Quercus acutissima and Quercus serrata had a low risk of crown fire, as well. When analysing risk of fire depending on a duration of flame, also, Quercus dentata had a low risk of stem fire, and Quercus variabilis Blume had a low risk of crown fire too. Lastly, when comparing risk of fire, according to heat release rates, Quercus acutissima had a low risk of stem fire, and Quercus acutissima and Quercus dentata had a low risk of crown fire, as well. In conclusion, it was observed that as fire-resistant species, Quercus serrata and Quercus dentata have a low risk of ignition, Quercus variabilis Blume has a short duration of flame after discharging ignition when a forest fire occurs, and Quercus acutissima, Pinus Rigida and Antipathes japonica Brook have low heat release rates.

• Korean Journal of Environmental Biology
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• v.36 no.2
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• pp.206-216
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• 2018

We analyzed the effects of spatio-temporal variation in the leaf production of oaks on the density and species richness of herbivores, as well as the consumption by herbivores in the east coastal region of Korea, which is an area that has been damaged by forest fires. The main herbivore that feeds on oak leaves was moth larvae. In mid-August the insect larvae showed the highest density and species richness. Approximately 60.5% of total plant-eating insect larvae were present from August to September 2011. Oak leaf production was at its peak from July to August, and the peak damage caused by herbivores was from August to September. Depending on the investigation timing and site of the survey, oak leaf production, larval densities, and species richness showed large variations. The average production of oak leaves between July and August was estimated to be $0.96ton\;ha^{-1}$. The production of oak leaves during this period also showed spatial variations ranging from 0.34 to $1.89ton\;ha^{-1}$. In August, the consumption of oak leaves by the herbivores showed spatial variations ranging from 0.15 to $1.51ton\;ha^{-1}$. Where oak leaves had a higher yield, they tended to increase in density and species richness of the herbivores. As the production of oak leaves increased, so did the overall consumption and consumption rate by the herbivores. This means that the production of oak leaves is highly related to time and space, and there is a concentration response in which the new individuals gather. Research into the spatio-temporal heterogeneity of the food sources and their effects on the higher levels of the food web can help us quantitatively understand and evaluate the structure and functions of the burnt ecosystem that is caused by forest fires.

• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.2
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• pp.127-134
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• 1999

This study was performed to obtain the basic data to present rational silvicultural tending plan. It makes these widely distributed pine-oak mixed stand and each of pure stand in middle province on object of this study and do comparative analysis of light condition about stand parameter and natural regeneration according to each slope(north, west and south) conditions of location in central part of South Korea. Sample plots for pine-oak mixed stand and pine and oak pure stand were established on each of southern, northern and western slopes based upon site and growth conditions of the slope. Sample plot was a circle of 0.05ha with a diameter of 25.24 m. A sample plot has between 30 and 40 tree in it. Total 23 sample plots were established; 9 pure pine stands, 8 pine-oak mixed stands. and 6 pure oak stands across lower, middle, upper parts of slopes. Relative light intensity within a stand was' measured by crown- photo(fish-eye lens; 180$^{\circ}$) system through fish-eye lens and by comparing each plot with the denuded through PAR-sensor. The crown closure ratio of pure pine stand (75%) shows much lower than that of mixed stand (90.9%) and pure oak stand (93%). The relative light intensity within a stand showed an opposite result. The crown closure of mixed stands tended to become gradually low as the slope moves from the north to the south, but the relative light Intensity within the stand tended to rise. By analyzing the relationship between the relative light intensity within a stand and stand parameter, light intensity within a stand tended to decrease as the diameter and N/ha increase. Number of oak seedlings and light intensity within a stand is in a straight-line regression relation. In particular, the number of oak seedlings was the highest in mixed stands on the southern slope. But no single pine seedling was found. The unfavorable conditions of l0cm thick litter layer and low relative light intensity in a stand (ranging between 4% and 8%) is considered to prevent pine seeds from germinating.

• Journal of Korean Society of Forest Science
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• v.90 no.3
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• pp.242-248
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• 2001

Changes in land-use can affect soil organic matter content and fertility. We compared total soil carbon and nitrogen concentrations, soil respiration, and nitrogen availability under three land-use types in central Korea; conversion of old rice field to natural willow-maple (Salix-Acer) forest, conversion of old field to artificial Korean pine (Pines koraiensis) forest, and indigenous oak (Quercus spp.) forest. After 20 years of fallow the area of rice field conversion to forest had higher soil carbon and nitrogen concentrations in the soil depth of 0-10cm and 10-20cm than the areas of field conversion to Korean pine forest and indigenous forest. In general, soil carbon and nitrogen concentrations decreased with soil depth. Organic matter accumulation as a balance of input and decomposition seemed to be higher in the soil of previous rice field, and carbon and nitrogen accumulation was largely confined to the topsoil. Soil respiration rates were greatest at the area of rice field conversion to forest, and appeared to be related to soil carbon and soil moisture. Soil nitrogen availability measured by the ion exchange resin bag method differed significantly among land-use types; soil inorganic nitrogen ($NH_4{^+}+NO_3{^-}$) and ammonium availability were highest in the soil under indigenous oak forest followed by conversion of old field to artificial Korean pine forest and conversion of old field to natural willow-maple forest.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.4
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• pp.222-228
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• 2012

This study was conducted to determine the natural succession process after forest fire by comparing height, relative growth rates in height (RGH), and tree density of pine seedlings with different fire severity. In the area damaged by surface fire, tree density was highest during the first 5 years after fire. However, in the area damaged by crown fire, tree density rapidly increased during first 5 years after fire. Pine seedlings were found only on the place with ridges, barren soil, and the aspect of north. Annual height growth of pine seedlings was decreased with time in all study sites. The empty space in pine stands gradually decreased by the invasion of Quercus species. The forest fire altered the pine forest into oak forest rapidly. In contrast, pine seedlings invaded steadily on the oak forest in the rocky area or the area with ridges.

• Journal of Korean Society of Forest Science
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• v.99 no.5
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• pp.736-743
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• 2010

This study examined the ecological attributes of classified forest community by cluster analysis in the mixed forest of Mt. Seokbyung Experimental Forest of Gangwon-Do. The vegetation data were collected in randomly established 51 sample plots (2.04 ha) and analysis adopted the cluster analysis, importance value index, and Shannon's diversity index. Main results were as follows; 1) the study area was classified into 4 clusters (A, B, C and D). 2) The cluster A was dominated by Pinus densiflora with an importance value of 71.6%. The most dominant species in the cluster B and cluster C were Larix leptolepis (57.1%) and Quercus mongolica (40.2%), respectively. Finally, The cluster D was dominated by P. densiflora (30.6%) and Q. mongolica (31.0%) with the mixed forest. 3) In the P. densiflora community (cluster A), distribution of DBH class showed a reverse J-shaped curve. In the L. leptolepis community (cluster B), individuals of dominant species had the bell-shaped distribution. Oak species indicated uniform distribution of DBH class (under 25 cm) in the mixed P. densiflora - Q. mongolica community (cluster D). 4) The species diversity index of the communities in descending order were: Pinus densiflora - Q. mongolica community > Larix leptolepis community > Pinus densiflora community > Quercus mongolica community.

• Journal of Korean Society of Forest Science
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• v.63 no.1
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• pp.61-68
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• 1984

The oak-mushroom is one of the special minor products utilizing hardwoods, such as oaks in the mountaineous villages, as a food for health and export in Korea. However, oak-mushroom farmers have been faced the problems such as small cultivation scale, unskilled technique of production, management of cultivation, and low productivity. It is now a turning point presenting the optimum and reasonable management techniques to increase the productivity with consideration of balanced income and expenditure. This report analyzed the investment effectiveness of cultivation. The financial rate of return (FRR) of oak-mushroom cultivation is as high as 10.3 percent compared with that of other farmings. Moreover, the FRR remarkably increased with increased cultivation scales. The FRR could be highly improved if the price of both mushroom-logs and dried mushroom products, is stable and the cultivation techniques for higher productivity are developed. The policy providing the constant price of raw materials and mushroom products, and new advanced cultivation techniques enable the enhancement of investment for the oak-mushroom cultivation.

• Journal of Korean Society of Forest Science
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• v.106 no.3
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• pp.310-319
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• 2017

This study categorized the damaged trees by Supervised Classification using time-series-aerial photographs of Bukhan, Cheonggae and Suri mountains because oak wilt disease seemed to be concentrated in the metropolitan regions. In order to analyze the spatial characteristics of the damaged areas, the geographical characteristics such as elevation and slope were statistically analyzed to confirm their strong correlation. Based on the results from the statistical analysis of Moran's I, we have retrieved the following: (i) the value of Moran's I in Bukhan mountain is estimated to be 0.25, 0.32, and 0.24 in 2009, 2010 and 2012, respectively. (ii) the value of Moran's I in Cheonggye mountain estimated to be 0.26, 0.32 and 0.22 in 2010, 2012 and 2014, respectively and (iii) the value of Moran's I in Suri mountain estimated to be 0.42 and 0.42 in 2012 and 2014. respectively. These numbers suggest that the damaged trees are distributed in clusters. In addition, we conducted hotspot analysis to identify how the damaged tree clusters shift over time and we were able to verify that hotspots move in time series. According to our research outcome from the analysis of the entire hotspot areas (z-score>1.65), there were 80 percent probability of oak wilt disease occurring in the broadleaf or mixed-stand forests with elevation of 200~400 m and slope of 20~40 degrees. This result indicates that oak wilt disease hotspots can occur or shift into areas with the above geographical features or forest conditions. Therefore, this research outcome can be used as a basic resource when predicting the oak wilt disease spread-patterns, and it can also prevent disease and insect pest related harms to assist the policy makers to better implement the necessary solutions.