• Journal of Korean Society of Forest Science
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• v.89 no.2
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• pp.275-284
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• 2000

This study was carried out to analyze the mechanical properties of soil and the slope stability on the fill slope of forest road constructed in the regions which consist of igneous and metamorphic rock area. The results were summarized as follows. 1) Soil type by Unified Soil Classification System(USCS) was classified as SW in soil slope, GP in weathered rock slope, GP in soft rock slope for both types of parent rock, but gravelly soil slopes in igneous and metamorphic rock area were classified as SP and GW, respectively. 2) Dry unit weight was $1.34g/cm^2{\sim}1.59g/cm^2$, specific gravity 0.57~0.61, and void ratio 0.66~0.93 in the case of igneous rock area, a dry unit weight was $1.35g/cm^2{\sim}1.51g/cm^2$, specific gravity 2.67~2.77, and void ratio 0.78~1.01 in the case of metamorphic rock area. 3) The strength parameters such as internal friction angle(${\phi}$) and cohesion(c) were selected and tested for slope stability analysis. ${\phi}$ and c of soil in igneous rock area were within the range of $29.51^{\circ}{\sim}41.82^{\circ}$ and $0.03kg/cm^2{\sim}0.38kg/cm^2$, respectively, and $21.43^{\circ}{\sim}41.43^{\circ}$ and $0.05kg/cm^2{\sim}0.44kg/cm^2$ in metamorphic rock area, respectively. 4) Result of the slope stability analysis of forest road showed that, in the weathered rock slope of igneous rock and the weathered rock and soil slope of metamorphic rock area, the possibility of slope failure was high as safety factor was below 1.0.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.1
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• pp.59-67
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• 2004

This study was carried out to select proper species for early stage replantation in granite forest roads cut-slope. From one to fourteen year elapsed forest roads in eight regional areas of Gyeongsang-do and Jeolla-do, sample plots were selected, and their vegetations and environmental factors were investigated. Soil organic matter, total nitrogen, soil moisture content, and bulk density in the granite weathering soils were below 0.4%, 0.03%, 12.4%, and above 1.2g/$cm^3$, respectively. The result indicated that the soil was not good for plant growth. The environmental factors affecting distribution of species in the granite forest roads were the elapsed year, elevation, and cut-slope aspect. Invaded species with high frequency in the forest road cut-slope ordered Pinus densiflora, Lespedeza bicolor, Rubus crataegifolius, Alnus hirsuta, Youngia denticulata, Patrinia villosa, Artemisia princeps var. orientalis, Zanthoxylum schinifolium, and Dactylis glomerata. Herbs seeded in earth stage such as Dactylis glomerata, Eragrostis curvula, Festuca arundinacea, Lespedeza sp., and Amorpha fruticosa had changed into perennial herbs and shrubs such as Youngia denticulata, Patrinia villosa, Aster scaber, Patrinia scabiosaefolia, Melica onoei, Astilbe chinensis var. davidii, Chrysanthemum zawadskii var. latilobum, Pueraria thunbergiana, Stephanandra incisa, and Clematis apiifolia, and had changed into plants such as Artemisia princeps var. orientalis, Artemisia keiskeana, Miscanthus sinensis, Pinus densiflora, Rhododendron mucronulatum, Rubus crataegifolius, and Zanthoxylum schinifolium according to elapsed year of forest roads. Leguma such as Lespedeza sp., Pueraria thunbergiana, Amorpha fruticosa, etc., herbs such as Artemisia keiskeana, Artemisia princeps var. orientalis, Chrysanthemum zawadskii var. latilobum, Miscanthus sinensis, etc., and woody plants such as Pinus densiflora, Rubus crataegifolius, Rhododendron mucronulatum, etc., with foreign herbs were considered as proper species for replantation in granite forest road cut-slope.

• Korean Journal of Environment and Ecology
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• v.17 no.3
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• pp.201-209
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• 2003

This study was carried out to select proper species fur early stage replantation in forest road cut-slope. From one to fifteen years elapsed forest roads in four regional areas of Gyeongsangnam-do and Jeollanam-do, sample plots were selected, and their vegetations and environmental factors were investigated. Invaded species and plant coverage have increased with elapsed years. The occurrence rate of herbs have decreased, while the occurrence of trees have increased with elapsed years. The ordination analysis showed that distribution of species was influenced by the elapsed year, the slope angle of the cut-slope, elevation, and the direction angle of the cut-slope. Dactylis glomerata, Poa pratensis, Amorpha fruticosa, Lespedeza sp., Artemisia princeps var. orientalis, Duchesnea chrysantha, Miscanthus sinensis, Pueraria thunbergiana, Zanthoxylum schinifolium, Rhus chinensis, and Weigela subsessilis were considered as proper species for replantation in forest road cut-slope, besides the species used already. Seventy seven family, 190 genus, 233 species, 38 variety, and 271 species in total were counted as invaded plant species in the survey zone. Naturalized plants were 18 species. Invaded species are, with high frequency first, Rubus crataegifolius, Artemisia princeps var. orientalis, Zanthoxylum schinifolium, Pueraria thunbergiana, Pinus densiflora, Lespedeza maximowiczii, Lysimachia clethroides, Lespedeza bicolor, Youngia denticulata, Miscanthus sinensis, and Erigeron annuus.

• Journal of Korean Society of Forest Science
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• v.84 no.2
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• pp.239-246
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• 1995

This research aimed at the contribution to obtaining the scientifical data which were required for planning she environmentally sound and sustainable management, particularly in the field of the logging road construction. Main natural environmental variables including natural vegetation, rainfall, soil runoff were measured in the logging road on-sites and analysed. This project was carried out at the (mt.)Paekunsan Research sorest of Seoul National University, located in Gwangyang, Chollanam-do in southern part of Korea, from 1993 to 1994. 1. The explanatory variables for erosion and sedimentation on logging road surface were accumulated rainfall, erosion distance, cross-sectional gradient, and soil hardness. The erosion and sedimentation on logging road was increasing positively in proportion to the accumulated rainfall, soil distance from starting point of the logging road, and cross-sectional gradient. 2. On cut-slope of logging road, cut-slope shape, part of the slope, plant coverage, soil hardness, sand content, accumulated rainfall, clay content, and silt content were effective factors. Cut-slope erosion and sedimentation on logging roam increased as with the lower plant coverage, the lower accumulated rainfall, the high sand content in the soil. 3. On fill-slope of logging road, there were three significant variables such as total rainfall and number of rainfall-storm. Fill-slope erosion and sedimentation had a positive correlation with the amount of rainfall, the number of rainfall, the soil hardness. 4. The total erosion and sedimentation on logging road were $5.04{\times}10^{-2}m^2/m^2$ in logging road construction year, $7.37{\times}10^{-2}m^2/m^2$ in next year. The erosion and sedimentation on logging road surface were 32.7% of total erosion and sedimentation on Logging road in construction year, and 57.1% in next year, respectively. The erosion and sedimentation on cut-slopes were 30.4% on logging road in construction year, fill-slopes of total erosion and sedimentation and 21.0% in next year, respectively. The erosion and sedimentation on fill-slopes were 36.9% on logging road in construction year, 21.9 in next year. To decrease the erosion and sedimentation at the logging road from the beginning stage of construction, the effective revegetation works should be implemented on the cut-slope and fill slopes, and erosion control measures such as optima. road design must be constructed on read surface.

• The Journal of Engineering Geology
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• v.27 no.2
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• pp.125-132
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• 2017

Approximately 64 percent of Korean territory is covered with mountains, and there is occurred a continuous mountain disaster such as landslide, debris flow and slope failure around mountain slopes due to heavy rainfall and typhoon in the summer season. Even in such a reality, the development of mountain areas is being carried out through the development and expansion of social infrastructures centered on mountain areas, but systematic management is insufficient. Constructions of a forest road facility for mountain slopes can be a cause of mountain disasters intensively in the summer season due to artificially changing the mountain area. In this unstable mountain environment, efforts to build a disaster-resistant environment are urgently needed. This research is to analyze the stability of mountain slopes according to soil depth (1~5 m) and mountain slope ($20{\sim}60^{\circ}$) considering the characteristics of rainfall infiltration under extreme rainfall conditions. As a result, the stability of the mountain slope was found to be different according to the depth of soils and the saturation area of the soil layer. As well as the stability of the mountain area was found to be lower than that of the natural mountain area. Specially, rainfall infiltration occurs at the upper slope of the forest road. For this reason, the runoff phenomenon of rainfall infiltration water occurs clearly when the depth of soil layer is low.

• Journal of Korean Society of Forest Science
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• v.80 no.3
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• pp.317-325
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• 1991

Route projection of forest road involves several constraints ranging from construction cost to environmental impacts. This study is designed to assess the capability of computer-assisted map analysis techniques for deriving several alternatives of forest road planning. Three cartographic models are presented to address the limit of slope, soil erosion, and aesthetic value in designing forest roads over a relatively small size of mountainous forest. Primary spatial analysis techniques used are distance measurements and connectivity analysis. The fundamental approach used was to generate a set of friction maps in which each friction map represents a combined restriction for a forest road projection. Products of the spatial analysis are compared by both qualitative and quantitative methods. The results demonstrate that computer-assisted map analysis has a potential to solve rather complex problems of forest road planning by providing several alternatives effectively.

• Korean Journal of Environment and Ecology
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• v.37 no.5
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• pp.367-391
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• 2023

This study was conducted for 10 years from 2012, which is a year before the forest road construction in Minjujisan, to 2022 to analyze annual changes in flora and vegetation before and after the forest road construction and to provide strategies for management. The plant communities in the research sites along the forest road showed the differentiation between slopes with Quercus mongolica community on the northwestern slope and Quercus variabilis and Larix kaempferi communities on the southwestern slope. A total of 212 taxa have increased for number 7 between before and after the construction from a total of 66 taxa (44 families, 59 genera, 51 species, 13 varieties, and 2 forma) in 2012 and 207 taxa (71 families, 153 genera, 176 species, 27 varieties, and 4 forma) in 2015 to 278 taxa (78 families, 172 genera, 242 species, 1 subspecies, 31 varieties, and 4 forma) in 2022. It is noteworthy that the vegetation cover and the introduction of new taxa had been expanded in the sites adjacent to the construction, which is likely caused by the significantly increased amount of light and the introduction of annual herbaceous and naturalized plants after the construction. The results of 10 years of current study reveal that the vegetation cover and the number of new taxa had rapidly increased in earlier years after the construction, slowly decreased later on, and finally formed a stable forest with the increase in the ratio of dominant species. The vegetation cover of the herbaceous layer immediately increased on the slopes along the forest road for a few years after the construction although it had continuously decreased while that of the shrub layer quickly increased. It was shown that on the hillslope the vegetation cover of tall- and low-tree layers increased whereas that of herbaceous and shrub layers rapidly decreased.

• Journal of Korean Society of Forest Science
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• v.76 no.4
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• pp.348-356
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• 1987

A new simple method to estimate the earth quantity which is basic data for making the plan of mountain forest road is tried to develop as one of ways to reduce time cost of plan making. The zero-line surveying method, the concept of 2/3 road width in cut-away part and of same quantity between cut-away and fill-up earth which are the backgrounds to develop this method is introduced and explaned also it's theoritical propriety. Under the precondition which have to apply above concepts for constructing the mountain forest road the exchange table for estimating the earth quantity is made like table 3 and 4 through being calculated by a trigonometric function. Table 3 can be used to estimate the earth quantity on the cut-away road-width according to slope of terrain and different road-width, and table 4 can be applied to calculate the quantity of cut-away earth when to know the road-width of cut-away. When using these tables the performance of field surveying and office work for road plan will be highly increased.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.1
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• pp.19-27
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• 2002

To investigate the dominant species and factors related with plant coverage by road structures and forest environment factors, forest roads elapsed from one year to twelve year after construction had been selected in six county(Gochang-gun, Muju-gun, Imsil-gun, Jangsu-gun, Jeongup-shi and Jinan-gun), and 20m segments were continuously set up in each road. The results obtained from this study are summarized as follows: The species diversity of Gochang, Muju, Imsil, Jangsu, Jeongup and Jinan were 1.304, 1.267, 1.308, 1.193, 1.289 and 1.018, respectively. In process of years, plant coverage was increased gradually and average of plant coverage was 15.3% in forest roads which elapsed three year, and was 86.5% in forest roads which elapsed nine year after construction. The dominant species in the cutting slope of surveyed area were covered with Arundinella hirta, Pinus rigida, Miscanthus sinensis var. purpurascens, Artemisia princeps var. orientalis, Pinus densiflora, Oplismenus undulatifolius, Rubus coreanus, Lysimachia clethroides, Lespedeza bicolor, and Alnus hirsuta of the 152 species. The high correlated factors between plant coverage and variables in cutting slopes appeared elapsed year, soil hardness, mean annual precipitation, vertical grade, inslope and arid humidity in surveyed area.

• Journal of Korean Society of Forest Science
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• v.97 no.4
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• pp.437-444
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• 2008

This study has intended to evaluate the forest recreation functions to seek methods to designate the recreational areas inside a recreation forest. This study has Mt. Chung-ok in Korea as a study area to which Quantification method II as a valuation measure was applied. This study also has chosen a degree of recreational utility as an external criterion and six factors including Forest type, Forest age, Slope, Riparian area, Road, and Facility for the 173 stands in this area. As a result, absolute discriminated success rate was obtained, so that the first and second estimated correlation ratios were 82% and 74%, respectively. Road and Slope had great influences on the potential power of recreational functions. In the category, recreational function was more influenced by the existence of road and the lower degree of slope. Also, this study has drawn an evaluation map, which displayed the potential power of recreational functions by classifying three discrimination points such as H(High), M(Medium), and L(Low) through calculating the degree of recreational utility of the recreation forest for the stands by applying an estimation formula of recreational function in the stands. This study seems to be worthwhile in terms of actual, experimental, and intuitive interpretation for the degree of recreational utility calculated by using Quantification method theory.