• Journal of the Korean Geotechnical Society
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• v.26 no.10
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• pp.27-38
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• 2010

In every summer season, most of the slope failures and debris flows occurr due to seasonal rain, typhoon, and localized extreme rainfall in Gangwon Province where 83% of the area is of mountain region. To investigate the slope-hazard triggering rainfall characteristics in Gangwon Province, slope hazard data, precipitation records, and forest fire data were collected and the DATABASE was constructed. Analysis results based on the DATABASE showed that many slope hazards occurred when there was little rainfall and the preceding rainfall had more effect on the slope hazard than the rainfall intensity at the day of hazard. It also showed that the burned area by forest fire was highly susceptible to slope hazard with low rainfall intensity, and the slope hazard in burned area showed highest frequency, especially, under the rainfall below 2-year return period.

• Journal of Korean Society of Forest Science
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• v.77 no.1
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• pp.1-9
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• 1988

To analyze phytosociological characteristics of the Mt. Namsan nature park, Seoul, vegetation structure of north-east and south-west slopes, competition capability among species, vegetation structures of afforested species were studied with belt-transect and quadrat methods. And management plan of each vegetational zone was proposed by the results of this study and the other previous reports. Numbers of species and individuals of south-west slope were greater than those of north-east slope. But species diversity of northeast showed stability of 1.0, while that of south-west showed instability from 0.8 to 1.3. The floristic dissimilarity coefficient between two slopes showed 70-80% in which species composition between two slopes was much different. Quercus mongolica was a dominant species at north-east slope and Pinus densiflora at south-west slope. Competition capability among major species was resulted in deciduous trees>Robinia pseudoacacia>Populus alba ${\times}$ glandulosa>Pinais densiflora, Quercus mongolica>deciduous trees>Pinus densiflora. Afforested vegetation at the Mt. Namsan, especially Pinus koraiensis, Abies holophylla, Picea abies, etc showed poor growth rate. The goal of the Nam-san nature park management is to conserve natural ecosystem as it is and, if necessary, to accerlerate restoration of the disturbed ecosytem to its nature by minimum energy input as possible. Management proposal was made for six vegetational management zone ; P. derasitZoru forest zone, Q. mongolica forest zone, deciduous forest zone, afforestation zone, R. pseduoacacia zone and landscape planting zone.

• Korean Journal of Environmental Biology
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• v.25 no.4
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• pp.363-369
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• 2007

To understand property of distribution restricted at northern slope of Corylopsis coreana, we investigated process of sedentary formation from seed germination to seedling and its micrometeorological factors in Cheongsogol, Suncheon in Korea. The germination tests were carried out in-situ and manipulated condition, respectively. Air and soil temperatures, relative humidity, soil water contents and PPFD were measured in southern and northern slopes for four seasons. The seeds did not shown difference in germination to azimuth slope. However, seedling in the northern slope should have taken advantage on the sedentary stage of seedlings because there was low temperature and high humidity during the spring. At the southern slope, the seedlings seemed to have a disadvantage on high temperature and low humidity in spring season. Accordingly, the formation of Corylopsis coreana population is influenced by microclimatic factors, especially in low temperature and high humidity at the sedentary stage of the germinated seedlings.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.6_1
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• pp.529-538
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• 2012

By using an algorithm derived by a multiple linear regression analysis, a technique for filtering was developed; and by using the developed technique, the results of conducting filtering of the raw data collected via scanning with a terrestrial LiDAR the actual sloped terrain was analyzed. As such, when filtering was applied by dividing the observation areas into two areas with the topographical line as a reference in order to improve the filtering accuracy, it was seen that the filtering accuracy improved by about 8.73% as compared to when filtering was applied without dividing the observation area. In addition, considering the fact that the accuracy improved by 5~7% when the sloped sides of a multicurvature topography were divided and a complex filtering applied as compared to when filtering was applied for the entire area or by regions, it can be asserted that the accuracy was higher when a complex filtering was conducted by dividing the sloped areas where the slope is not constant due to the multi-curvature of topography.

• Journal of Korean Society of Forest Science
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• v.94 no.1 s.158
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• pp.26-33
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• 2005

The study was carried out to provide information about growth and ecological characteristics by site types of natural deciduous forest in Pyeongchang, Gangwon Province. The data were collected from four aspects(the East, the West, the South, and the North) with three elevation(higher than 1.000 m, 700~1,000 m, lower than 700 m) and three topographical conditions(ridge, hill, and valley). Growth parameters by site types were evaluated based on the growth performances of dbh for the last 5 to 10 years; which were also estimated based on both Pressler and Schneider formulae. In addition, ecological characteristics such as Shannon-Wiener's diversity index, evenness index and richness index were analyzed by site types. The management methods by site types were suggested by considering stand density, growth patterns, and ecological characteristics. It was found that the stands on the South and the East are necessary the tending practices to improve growth and ecological characteristics. On the other hand, the West and the North needed the tending practices focusing on stand density management to increase growth rate rather than ecological management. It was also found that the area lower than 700 m in elevation showed Higher growth rate than other areas. As a management standard considered in terms of growth rate, it was suggested that tending practices should be applied to the stands of which growth rate for the last 5 to 10 years were lower than 2%. Considering topographical conditions, valley area showed better ecological characteristics than both ridge and hilly areas. Consequently, it was revealed that the valley areas were suitable for the ecological management.

• Proceedings of the KSEEG Conference
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• 2003.04a
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• pp.269-272
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• 2003

하천에 토사가 유입되는 가장 중요한 요인은 주변 지역의 사면에서의 토양의 침식작용이며 이러한 현상은 다양한 요인들에 의해 영향 (사면경사, 사면식생, 토양 입도, 사면거칠기 등)을 받지만 주로 물, 특히 강우에 의해 크게 좌우된다. 그러므로 정확한 강의 양과 강우 강도, 이에 따른 토양의 침식량을 정량화하는 것이 중요하다. 이번 연구에서는 이러한 다양한 조건에 따라 토양의 침식이 어떠한 특성을 갖고 발생하는지를 파악하고자 하였다. (중략)

• Tunnel and Underground Space
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• v.18 no.1
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• pp.20-32
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• 2008

The study shows a method called a square-inventory method, which is a better and faster method than scanline survey and window method for an analysis of slope stability. The study area is located in the Changri area, Boeun-Gun, Chungbuk, and consists of many formations of the Okcheon Supergroup. Various types of failure are observed from the phyllite including the rocks in the study area. The physical properties of meta-sedimentary rocks are that minerals of the rocks are composed of microcrystalline quartz and sericite, which are arranged parallel to bedding (or schistosity) and crenulation cleavage. Therefore, such properties affect geotechnical ones of the rock. The slope stability are analyzed by selecting 3 areas, each of which are divided into 2 or 3 slopes of $1m{\times}1m$ area that represent each of 3 investigation sites. The possibility of wedge and toppling failure is very high in all 3 areas by using square-inventory method. Although possibility of plane failure is weak in the investigation site 2, the plane failures are frequently found from the slope of site 2. The bedding (or schistosity) plane and cleavage, another types of discontinuity coexist in meta-sedimentary rocks uulike igneous rocks, and therefore are important factors to be considered together with joint structures in th ε analysis of slope stability.

• Land and Housing Review
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• v.2 no.2
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• pp.157-162
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• 2011

This paper presents the landslide characteristics occurred in Hoengseong, Gangwondo and around July 16 in 2006, caused by heavy rainfall and antecedent precipitation by two typhoons of Ewiniar and Bilis. The main causes of landslides were antecedent precipitation between July 12 to 13, resulting in weakening grounds by increasing the degree of saturation previously, and the additional heavy rainfall between July 15 to 16. Most of landslides at natural slopes were transitional failures occurred along the boundary between residual weathered soil in shallow depth and hard mother rock. From the results of conclusive analyses for 100 sites in Hoengseong region where landslides occurred, the slope length of landslide and slope width were less than 100m with 87% of frequency and 30m with 74% of frequency, respectively. The average value of slope angles was $24^{\circ}$.

• Journal of Korean Society of Forest Science
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• v.89 no.5
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• pp.552-563
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• 2000

The aim of this study was to characterize the forest vegetation and site of Odaesan National Park for ecological forest management. The vegetation could be divided into two forest community groups, seven forest communities, and several subcommunities. South exposed, dry slopes were covered with forests of the Quercus mongolica-Acer pseudosieboldianum community group. Quercus mongolica-Acer pseudosieboldianum community group could be subdivided into ${\bullet}$ Rhododendron mucronulatum var. ciliatum community on dry sites, especially on south or south-westly exposed ridges or convex slopes; ${\bullet}$ Lespedeza${\times}$tomentella community on south exposed slopes, at low altitudes in the eastern part of the study area; ${\bullet}$ Carex humilis-Maackia amurensis community on south exposed slopes up to the montane region; ${\bullet}$ Quercus mongolica-Acer pseudo-sieboldianum typical community on south exposed middle and low slopes, and on upper and middle north exposed slopes; ${\bullet}$ Pimpinella brachycarpa community, preferably on moderately moist and cool sites. On north exposed, more humid and moist sites, forests of the Dryopteris crassirhizoma-Cornus controversa community group were found. This group was subdivided into ${\bullet}$ Acer tschonoskii var. rubripes-Acer tegmentosum community on moderately moist to moist, loamy soils on shady slopes; ${\bullet}$ Deutzia glabrata-Ulmus laciniata community on north exposed slopes with rocky soil and boulders, having high humidity. There are several rare and endangered species in Rhododendron mucronulatum var. ciliatum community, Carex humilis-Maackia amurensis community, Vicia venosa var. cuspidata subcommunity and Saxifraga punctata subcommunity, and the communities were located in azonal areas in topography. To protect the species, the areas should be categorized as an absolute conservation area, and any forest working should be prohibited in this area.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.541-545
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• 2010

식생이 소실된 산불 피해 지역에서 유실되는 토양의 식생회복에 따른 정량적인 변화를 파악하고, 사면토양과 유실토양의 성분분석을 수행하여 이화학적 특성을 파악하고자 한다. 산불 이후 10개의 조사구에서 강우에 의해 유실토양의 양을 측정한 후 토양을 건조시켜 보관하였다. 토양의 입도분석, 유기물함량, 건조밀도 등을 조사하였다. 그리고 전처리한 토양수는 ICP를 이용하여 Fe, Mn, P, Al, Zn, Na, Mg, K, Ca의 성분분석을 수행하였다. 산불 이후 시간경과에 따른 조사구별 식생 회복은 빠른 지역과 느린 지역으로 크게 구분한다. 재생이 불량한 지역은 재생이 왕성한 지역에 비해 상대적으로 많은 양의 토양이 유실되었다. 사면토양의 성분분석 결과 재생불량 지역의 성분함량이 가장 작았으며, 재생왕성 지역은 비피해지에 비해 성분함량이 대체로 높았다. 유실토양의 성분분석 결과 식생회복이 느린 조사구에서 영양염류 함량이 대체로 낮았다. 그러나 식생회복이 느린 조사구에서 많은 양의 토양이 유실되기 때문에 정량적인 영양염류의 소실량은 가장 많았다. 따라서 지표식생이 없는 지역은 다량의 토양유실로 인해 다량의 영양염류가 소실되어 식생 재생을 더디게 만드는 것으로 판단된다.