• Journal of Korean Society of Forest Science
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• v.45 no.1
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• pp.11-25
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• 1979

There was much mass movement at many different mountain side of Peong Chang area in Kwangwon province by the influence of heavy rainfall through August/4 5, 1979. This study have done with the fact observed through the field survey and the information of the former researchers. The results are as follows; 1. Heavy rainfall area with more than 200mm per day and more than 60mm per hour as maximum rainfall during past 6 years, are distributed in the western side of the connecting line through Hoeng Seong, Weonju, Yeongdong, Muju, Namweon and Suncheon, and of the southern sea side of KeongsangNam-do. The heavy rain fan reason in the above area seems to be influenced by the mouktam range and moving direction of depression. 2. Peak point of heavy rainfall distribution always happen during the night time and seems to cause directly mass movement and serious damage. 3. Soil mass movement in Peongchang break out from the course sandy loam soil of granite group and the clay soil of lime stone and shale. Earth have moved along the surface of both bedrock or also the hardpan in case of the lime stone area. 4. Infiltration seems to be rapid on the both bedrock soil, the former is by the soil texture and the latter is by the crumb structure, high humus content and dense root system in surface soil. 5. Topographic pattern of mass movement spot is mostly the concave slope at the valley head or at the upper part of middle slope which run-off can easily come together from the surrounding slope. Soil profile of mass movement spot has wet soil in the lime stone area and loose or deep soil in the granite area. 6. Dominant slope degree of the soil mass movement site has steep slope, mostly, more than 25 degree and slope position that start mass movement is mostly in the range of the middle slope line to ridge line. 7. Vegetation status of soil mass movement area are mostly fire field agriculture area, it's abandoned grass land, young plantation made on the fire field poor forest of the erosion control site and non forest land composed mainly grass and shrubs. Very rare earth sliding can be found in the big tree stands but mostly from the thin soil site on the un-weatherd bed rock. 8. Dangerous condition of soil mass movement and land sliding seems to be estimated by the several environmental factors, namely, vegetation cover, slope degree, slope shape and position, bed rock and soil profile characteristics etc. 9. House break down are mostly happen on the following site, namely, colluvial cone and fan, talus, foot area of concave slope and small terrace or colluvial soil between valley and at the small river side Dangerous house from mass movement could be interpreted by the aerial photo with reference of the surrounding site condition of house and village in the mountain area 10. As a counter plan for the prevention of mass movement damage the technics of it's risk diagnosis and the field survey should be done, and the mass movement control of prevention should be started with the goverment support as soon as possible. The precautionary measures of house and village protection from mass movement damage should be made and executed and considered the protecting forest making around the house and village. 11. Dangerous or safety of house and village from mass movement and flood damage will be indentified and informed to the village people of mountain area through the forest extension work. 12. Clear cutting activity on the steep granite site, fire field making on the steep slope, house or village construction on the dangerous site and fuel collection in the eroded forest or the steep forest land should be surely prohibited When making the management plan the mass movement, soil erosion and flood problem will be concidered and also included the prevention method of disaster.

• Journal of the Korean Wood Science and Technology
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• v.42 no.6
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• pp.682-690
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• 2014

In order to improve the thermal stability of wood plastic composites (WPC), thermal degradation behavior of WPC in this study was investigated by the addition of wood flour and fire retardant after hybridization of wood flour and ammonium polyphosphate (APP) into polypropylene (PP) matrix. Thermal degradation behavior of all formulations was analyzed with thermogravimetric analyzer under nitrogen environment at heating rate of $10^{\circ}C/min$. As the thermal degradation temperature of wood flour is lower than that of PP, char layer formed by the wood flour decreases the speed of heat transfer to PP. In addition, the char layer increases the 2nd thermal degradation temperature and decreases the 2nd thermal degradation speed. The WPC treated with APP increases the 1st and 2nd degradation temperatures. In the case of WPC with high loading level of wood flour, the 1st thermal degradation temperature and 2nd thermal degradation rate were increased by the addition of APP, and then the amount of remnants at high temperature was increased by the increase of the APP loading level. In the case of WPC treated with APP, the amount of the remnants at high temperature was increased with the increase of wood flour content from 10 wt% to 50 wt%, indicating that char formation of the APP and wood flour occurred at the same time, resulting in high thermal stability effect by the increase of wood flour content.

• Journal of the Korean Wood Science and Technology
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• v.40 no.1
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• pp.19-25
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• 2012

The fire retardant bamboo charcoal (BC) boards were manufactured for interior building materials in this study, The BC boards were manufactured by mixing and pressing of the bamboo charcoal, expanded vermiculite, and inorganic binder. The combustion behaviors of the BC boards were investigated using a cone calorimeter at an incident heat flux of 50 kW/$m^2$. Three building materials (plywood, BC board of Japan, and gypsum board) were used to observe the burning behaviors of weight loss, total heat release rate, and maximum heat release rate. Surface test and toxicity evaluation of the BC board were also conducted. The weight loss of the BC board (12.0%) was lower than the nonflammable gypsum board (15.6%) after burning of 10 min. Total heat release of the BC was 3 MJ/$m^2$ (KS standard 8 MJ/$m^2$) and total heat release rate of the BC was 20 kW/$m^2$ (KS standard 200 kW/$m^2$). Therefore, the BC boards were adjustable for the third-grade flame retardant building materials. External appearance change and mouse toxicity were not found in the BC boards after the combustion test.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.2
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• pp.118-130
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• 2007

The steep-sloped agricultural land was severely damaged by rainfall events during July and August every year. The objective of this study was to investigate an effects of intensive rainfall to the soil properties of the steep-sloped agricultural land. Survey sites including the Sacheon myeon area were located in Gangneung, those were severely damaged from a forest fire in April 2000. Surveys were taken at these sites after two years of forest fire and severe rainfall events in August 2002, which included an event that poured with 870 mm of rainfall in a day. After this storm, soil erosion, burying, and flooding were observed. Severe soil loss was found at lower soil-depths, greater slopes, longer slope lengths, and concave landscapes. Soil loss and land slides were often found at areas with having a coarser textures, higher bulk densities, lower water holding capacity, and lower rates of soil aggregation. Crop growth stagnation was found at the site of crop restoration because of low soil fertility and poor drainage caused by the abrupt textural changes. In conclusion, it is necessary to manage the steep-slope agricultural land based on environmental impact assessment data of macro morphological and physical characteristics by intensive rainfall.

• The Korean Journal of Ecology
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• v.16 no.4
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• pp.429-438
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• 1993

This is a report on the early vegetation and the secondary succession in the burned area of SeobJe-Go1 of $IIwasan-MY\v{o}n,\;Y\v{o}ngch\v{o}n-Gun,\;Ky\v{u}ngsangbuk-do$ Province. The forest fire occurred on April 8, 1982 and the pine forest and its floor vegetation were burned down. The investigation was done six times from August 20, 1982 to August 13, 1983. The results are summarized as follows: the floristic composition of burned areas $B_1,\;B_2$, and unburned areas $U_1,\;U_2$ were composed of 25, 23, 32, and 27 kinds of vascular plants. respectively. The biological spectra showed the $H-D_1-R_5-e$ type in both the burned and unburned areas. The species of Arundinella hirta, Miscanthus simnsis var. purpurascens and Cares hurnilis var. nana were dominant species in the burned area, while Pinus densiflorrr, Corex humilis var. nana and Rhododendron mucronulatum var. ciliafum were dominant species in the unburned area. Degree of succession of the unburned area was comparatively higher than that of the burned area. Species diversity index and evenness index of the burned area were similar to those of the unburned area. Indices of similarity in sampling sites showed that $B_1\;and\;B_2$ stands were the most similar. pH, total nitrogen, available phosphorus and exchangeable potassium of soil increased but organic matter and total organic carbon decreased after fire.

• Fire Science and Engineering
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• v.29 no.4
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• pp.49-56
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• 2015

Toxic gases from five types of interior building materials were investigated according to Naval Engineering Standard (NES) 713. The materials were plywood, indoor wall coverings (wood wall plate members and pine wood), reinforced Styrofoam insulation, laminate flooring, and PVC. Specimens were measured using an NES 713 toxicity test apparatus to analyze the hazardous substances in combustion gas from the materials. We used the US Department of Defense standard (MIL-DTL, Military Standard) to calculate the toxicity index of the combustion gas. Emissions of $CO_2$ from all specimens did not exceed the NES 713 limit of 100,000 ppm. The amount of CO gas emissions from reinforced Styrofoam insulation was 6,098 ppm. 25 ppm and 49 ppm of formaldehyde were released from the reinforced Styrofoam insulation and PVC flooring, respectively. These values were less than the limit of 400 ppm. The highest emissions were from $NO_X$ emitted by plywood and were above the limit of 250 ppm. The toxicity index of the specimens were calculated as 5.19 for plywood, 4.13 for PVC flooring, 2.35 for reinforced Styrofoam insulation, 2.34 for laminate flooring, and 1.22 for indoor wall coverings (pine wood). Our research helps us to understand the properties of these five interior materials by analyzing the combustion gas and explaining the toxicity of constituents and the toxicity index. Also, it would be useful for giving fundamentals to guide the safe use of interior materials for applications.

• Korean Journal of Ecology and Environment
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• v.46 no.2
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• pp.251-264
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• 2013

This study was conducted to investigate the diversity of ectomycorrhizal fungi by surveying sites from June 2010 to October 2011. The obtained results from investigation were as follows. The total of 2 Kingdom 3 Phylum 6 classes 15 orders 34 families 59 genera and 107 species including saprophytic and ectomycorrhizal fungi was investigated. A total of 10 families 17 genera 49 species (801 ea.) of ectomycorrhizal mushroom was investigated. The mushrooms are classified into 28 families 51 genera and 99 species in Basidiomycota, 5 families 7 genera and 7 species in Ascomycota and 1 families 1 genera and 1 species in Amoebozoa. Dorminant species were Amanitaceae (14 species) followed by Russulaceae (12 species) and Boletaceae (11 species). The populaion ectomycorrhizal mushroom was highest in sites 1 and 2, and sites 4 and 5 occurrence rarely. The mushroom occurrence of ectomycorrhizal fungi was closely related to climatic conditions such as high air temperature and lots of rainfall from July to August. The environment factors which have a favorable influence of mushroom occurrence were soil pH, organic matter content of soil and air temperature of climatic environment.

• The Korean Journal of Ecology
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• v.24 no.1
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• pp.1-7
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• 2001

This study was carried out to examine the recovery of forest ecosystem by changes of soil chemical properties and soil microorganism at the burned areas of coniferous (Mt. Chocdae) and broad leaved forest (Samsinbong in Mt. Chiri). In the soil chemical properties of the burned area of Samsinbong, pH was 5.8, and contents of organic matter, total nitrogen, available P₂O/sub 5/, exchangeable K/sup ＋/, exchangeable Ca/sup ＋＋/ and exchangeable Mg/sup ＋＋/ were 7.42%, 0.73%, 28.5 ㎎/㎏, 1.3 me/100g, 13.3 me/100g and 2.2 me/100g, respectively. But they showed a tendency to decrease with time. In the soil chemical properties of the burned area of Mt. Chocdae, pH was 5.3, and contents of organic matter, total nitrogen, available P2O5, exchangeable K/sup ＋/, exchangeabe Ca/sup ＋＋/ and Exchangeable Mg/sup ＋＋/ were 6.42%, 0.25%, 24.4 ㎎/㎏, 0.7 me/100g, 3.7 me/100g and 2.1 me/100g, respectively, and they also showed a tendency to decrease with time. In contrast, they were not changed with time at the unburned areas. At the burned area of Samsinbong, soil microorganism showed to order of fungi (69×10⁴ CFU), actinomycetes (523×10⁴ CFU) and aerobic bacteria (291×10⁴ CFU), and at the unburned area, showed to order of actinomycetes (745×10⁴ CFU), fungi (594×10⁴ CFUU), and aerobic bacteria (160×10/sup 4/ CFU). At the burned area of Mt. Chocdae, soil microorganism showed to order of fungi (676×10⁴ CFU), actinomycetes (434×10⁴ CFU) and aerobic bacteria (350×10⁴ CFU), and at the unburned area, showed to order of fungi (461 ×10⁴ CFU), aerobic bacteria (328×10⁴ CFU) and actinomycetes (319×10⁴ CFU). Soil microorganisms of the aerobic bacteria, actinomycetes and fungi appeared at the burned areas were much more abundant than unburned areas. The aerobic bacteria appeared at the coniferous forest were also much more than the broad-leaved forest. The actinomycetes and fungi appeared at the broad-leaved forest were much more abundant than the coniferous forest.

• The Korean Journal of Ecology
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• v.8 no.2
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• pp.109-117
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• 1985

This report is a part of the investigations of the secondary vegetation successions carried out and the analysis of soil properties in the burned areas of forest. The fires-crown fire and surface fire-were occurred at April, 1978 and February, 1984. The investigations were carrited out from August 10. 1983 to September 25, 1984. The burned areas studied are located in southern slope of Mt. Ssalibagu (above sea-level, 590m), So-myon, Sungju-gun, Chollanam-do, Korea. The results are as follows: The floristic compositions of the burned area at the 5th year after the fires were 85 families, 250 genera, 321 species and 53 varieties. Among them, 85 families, 127 genera, 129 species and 30 varieties were found in the currently burned area. In all the sampling sites (10*10cm), 31 and 57 species were found in the currently burned and in the 5th years after the fires, respectively. Miscanthus sinensis var. purpurascens, Quercus serrata and Festuca ovina were dominant species in the both areas. Biological spectra in both the burned areas showed $H-D_1-R_5-e$ type. Degree of the succession(DS) was 412-884 in the 5th years passed burned area and it was high level. Species diversity index(H) was 0.59~1.13 and evennes index(e) was 0.43~0.79, these indexes between both areas were different considerably. Indexes of similarity between both areas were different, too, but that between $B_1$ and $B_6$ was the highest (CCj=0.5). Probably this phenomenon is due to the great numbers of the pine trees appeared simulataneously. Content of the organic matter, N, P, K and Ca of soil in the burned area at the 5th years after the fires was lower than that of soil in the currently burned area.

• Journal of Environmental Science International
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• v.23 no.6
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• pp.1121-1130
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• 2014

This study aims to find the perception and utilization of the citizen about the dryness watch warning (DWW) among special weather reports. For this we have made up a descriptive questionnaire including the perception, utilization of special weather reports. Using the SPSS 17.0 program, descriptive statistics, t-test, ANOVA and Scheffe test were used to analyze the collected data. The results are as follows; The perception of DWW is measured by 4 point Likert scale and the average is $15.97{\pm}3.70$ (percentile=57.0). This value shows that the awareness level is not that high and according to the occupation, college students show the lowest awareness and housewives show the highest awareness. According to the age, the teens and twenties show the lowest awareness and fifties and sixties show the highest awareness. Although the perception of the teens and college students are rather poor, there were many positive answers that it is necessary to establish the advanced disaster prevention plan according to the questionnaire about the utilization of DWW. Therefore, if we come up with an effective plan to improve the perception than we can expect a large-effect in terms of fire and forest fire prevention. The perception of DWW can be improved by providing weather information and weather related education program on TV or internet which have the high level of preference. Also, it is necessary to provide online and offline program of advertising education and disaster management education through the weather forecast bureau which is the host organization of delivering weather information.