• 한국방재학회:학술대회논문집
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• 2010.02a
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• pp.71.2-71.2
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• 2010

가을철 산불조심기간 중 영동지방 침엽수림에 대하여 임분밀도별 낙엽층, 부식층, 토양 상 하층에 대하여 연료습도 변화를 실측한 결과 낙엽층의 경우 소임분은 3일차 되는날 산불 초기 발화위험성이 나타났으며, 부식층의 경우 강우 익일 후 145-180%의 높은 연료습도를 보이고 있었으며, 소임분은 강우 후 6일차가 되어도 약 47%, 중 밀임분의 경우 60% 이상의 연료습도를 보이고 있어 산불 초기 발화위험성은 낮은 것으로 조사되었다. 토양 1층의 경우 강우 익일에는 30%-42%의 연료습도를 나타냈고, 6일 후에도 20% 이상의 연료습도를 유지하고 있는 반면, 토양 2층의 경우는 임분밀도, 시간경과와는 거의 상관없이 일정한 연료습도를 유지하고 있는 것으로 나타났다.

• Journal of Korean Society of Forest Science
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• v.48 no.1
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• pp.40-50
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• 1980

This research was carried out to examine the substitutional feasibility of low-priced materials produced in waste of forest instead of wheat flour which is extended for plywood adhesives. Wheat, pine bark, wood flour and pine foliage of coniferous trees or poplar foliage of hardwood species were selected and pulverized into 60-100 mesh minute powder after they were dried at $100-105^{\circ}C$ during 24 hours in the drying oven. The prepared particles as above were added to urea formaldehyde resin, urea-melamine copolymer resin and water soluble phenol formaldehyde resin in the ratio of 10, 20, 30 and 50%. After plywoods were processed by the above extending ratios, shear strength of extended plywoods were analyzed and discussed. The results obtained at this study were summarised as follows; 1. In the case of urea formaldehyde resin, both dry and wet shear strength of plywoods extended by wheat flour were shown the highest value. 2. Dry shear strength of urea-melamine copolymer resin was better than that of urea formaldehyde resin on the whole, while plywoods extended by wheat flour were shown excellent results. 3. Among 10% and 20% extensions of urea-melamine copolymer resin, the best results were shown by poplar leaves powder, wheat powder and wood flour. They had no significant difference statistically. 4. In the case of water soluble phenol formaldehyde resin, although dry shear strength of pine leaves powder was higher than that of wheat flour in the ratio of 10%, there was no significant difference between them in the ratio of 10 and 20%. 5. Among 20, 30 and 50% extensions of water soluble phenol formaldehyde resin, wet shear strength of wood flour and bark powder was higher than that of wheat flour. Wet shear strength of wood flour in the ratio of 10% was shown the same tendency as above.

• Journal of Energy Engineering
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• v.23 no.3
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• pp.241-246
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• 2014

This study is to compare characteristics of saccharification reactions applying to enzymatic hydrolysis of pretreated fallen leaves for bio-ethanol production. It experimented pretreatment of acid, alkaline in the chemical. This experiment includes preteatment of acid and alkaline in chemical, soaking, shaking and autoclaving method, which were applied to biomass. In result, the glucose production from alkaline-NaOH method was 263 mg glucose/ g biomass comparing with them of acid-HCl method. Thus, alkaline-NaOH method is superior than the acid-HCl method for chemical preteatment of fallen leaves. Also, when various chemical treatments were compared, they were all. Based on the results of this study, we found that leaves, one of biomass, are possible in pretreatment and enzymatic hydrolysis process, and they are likely to affect bio-ethanol production in the future.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.3
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• pp.181-187
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• 2014

Forest floor is one of most distinctive features of forest ecosystem, which provides plants and soil microbes with nutrients, and controls hydrologic condition within the floor by intercepting water during a rainfall event and evaporates back into the atmosphere. In this study rainfall interception loss by decomposed forest floor of a deciduous forest has been experimentally estimated using rainfall simulation experiments. Litter-decomposing fungi were incubated on deciduous forest floor samples for the experiment purposes. On a deciduous floor, a $4.22mm{\cdot}kg^{-1}{\cdot}m^2$ of rain was intercepted immediately before rain ceased. Minimum values of interception loss ranged from 1.62 to $2.41mm{\cdot}kg^{-1}{\cdot}m^2$, with an average of $1.87mm{\cdot}kg^{-1}{\cdot}m^2$. Mann-Whitney test showed that decomposing fungi on the forest floor influenced on rainfall interception capacity.

• Journal of The Korean Society of Grassland and Forage Science
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• v.9 no.1
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• pp.43-47
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• 1989

草地生態系에 있어서의 칼리 (K)의 動態에 관한 硏究의 한 부분으로서, 草地土壞의 表面에 놓인 牧 草落葉의 分解에 따른 칼리의 溶出狀況을 그외의 無機養分의 溶出과 比較하여, 칼리溶出의 特性을 알아 낼 目的으로 실험을 수행했다. 초지토양의 표면에 놓인 牧草葉은 1年의 시험기간중에 當初乾物量의 약30%로 分解되었으며, 그分解速度는 月隣水量보다는 平均氣溫과 더 높은 相關關係를 보였다. 낙엽분해에 따르는 植物體로 부터의 養分溶出은 칼리>인(P)>마그네슘(Mg), 질소(N)>칼슘(Ca)의 順l이었다. 칼리와 인은 1個月 경과후에 當初含有量의 40%와 45%로 현저하게 減少되었으며, 칼리는 그 以後에도 牧草의 分解에 따라 계속해서 溶出되어 9個月 째에는 1%로 減少되었다. 마그네슘과 질소는 목초의 분해와 거의 一致해서 溶出되었으나, 칼슘은 낙엽의 분해가 진행되어도 當初含有量에서 큰 減少가 일어나지 않았다. 以上의 結果로 부터 질소를 포함한 無機物의 溶出은 牧草의 分解와 대체로 같은 傾向을 나타내는 것을 알았으며, 칼리의 溶出은 특히 牧草落葉의 分解初期에 많다는 것을 알았다. 따라서 牧草落葉으로부터의 칼리의 溶出이 草地生態系에 있어서의 칼리의 再循環에 큰 役割을 하는 것으로 생각되어 졌다.

• 한국생태학회:학술대회논문집
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• 1998.05a
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• pp.109-109
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• 1998

• Proceedings of the Zoological Society Korea Conference
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• 1994.10a
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• pp.126.2-126
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• 1994

• Proceedings of the Korean Society of Soil Zoology Conference
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• 1998.03a
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• pp.8-8
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• 1998

• The Korean Journal of Soil Zoology
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• v.6 no.1_2
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• pp.25-31
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• 2001

Oribatid mite communities in the process of litter decomposition were analyzed In Korean pine (Pinus koraiensis) forests of Namsan and Kwangreung, which were supposed to be under different environmental selective pressures. Oribatid mites were collected bimonthly from the litter bags (mesh size 0.4 mm, 1.7 mm) which was set up in the forest floor of study sites. This study had been carried out from Jan., 1997 to Sept., 1998. Species abundance of Kwangreung (mesh size 1.7 mm) was significantly higher than that of Namsan (mesh size 1.7 mm), but total no. of species did not exceed 30 species in all study sites. Concerning body length, medium sized oribatid mites (0.3-0.7mm) were more abundant than small ( < 0.3 mm) and large ( > 0.7 mm) sized mites. In Kwangreung, species whose body lengths were 0.2 mm to 0.5 mm were major group. However, a little larger species than Kwangreung's major group were dominant in Namsan. Sorenson similarity index and cluster analysis suggested that there were qualitative and quantitative differences in species composition in Namsan and Kwangreung. More species were collected in May through September than the other sampling times, but the pattern was rather different between first year and second year. Newly immigrant species were high in May in the first year and many of them regained on next year. Diversity indices suggested that species diversity of Kwangreung was higher than that of Namsan. Nearly 70% of total individual abundance was occupied by several dominant species in Namsan and Kwangreung . In the litter bags of mesh size 1.7 mm, the most dominant species was Trichogalumna nipponica in Namsan and Kwangreung, but in the litter bags of mesh size 0.4 mm in Kwangreung it was Ramusella sengbuschi which is smaller than T. nipponica. And important species related to litter decomposition were selected as follows; T. nipponica, Epidamaeus coreanus, Scheloribates latipes, Ceratozetes japonicus, Ramusella sengbuschi, Eohypochthonius crassisetiger, and Cultroribula lata.

• The Korean Journal of Ecology
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• v.23 no.1
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• pp.33-37
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• 2000

Mass loss and changes of mineral nutrients during decomposition of Lepista nuda for 7 weeks from October 7 to December 28 in 1998 were investigated in an oak stand in Kongju, Korea. Content of nitrogen, phosphorus, potassium, calcium and magnesium of the fresh L. nuda was 67.8, 4.1, 47.3, 0.4 and 1.5 ㎎/g, respectively. Content of nitrogen, phosphorus and potassium in L. nuda were much higher than those in leaf litter. After 7 weeks, remaining mass was 35%. Nitrogen, phos- phorus and potassium increased till 5 weeks and then decreased rapidly, however, calcium and magnesium steadily increased during the experimental period. Nitrogen and phosphorus showed a short period of immobilization, and calcium showed no immobilization period during decomposition. After 7 weeks, remaining N, P, K, Ca and Mg was 26.6, 37.5, 28.5, 35.0 and 91.0% of the initial content, respectively. Nutrients could be relocated spatially during the formation and decomposition of fruiting body of Basidiomycetes.