• Journal of Korean Society of Forest Science
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• v.98 no.4
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• pp.379-391
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• 2009

This study was carried out to classify forest vegetation structure of Mt. Munsu and Mt. Okseok from May to September in 2008 using phytosociological analysis methodology of Z-M school under the purpose of furnishing basic materials for rational and scientific forest management. Total of one hundred five study sites (quadrats) was investigated in the area. Quercus mongolica community group was divided into 5 communities such as Pinus densiflora for. erecta community, Hydrangea serrata for. acuminata community, Salix gracilistyla community, Pinus koraiensis community and Larix kaempferi community. Pinus densiflora for. erecta community was subdivided into Rhododendron micranthum group, Quercus variabilis group and Pinus densiflora for. erecta typical group. Hydrangea serrata for. acuminata community also into Ligularia fischeri group, Deutzia glabrata group (into Juglans mandshurica subgroup, Prunus maackii subgroup and Callicarpa japonica subgroup). Accordingly, the vegetation of the study areas could be described as 1 community group, 5 communities, 5 groups, and 3 subgroups and as 10 units in total. Classified vegetation units were highly correlated with altitude and topography. According the analysis of interspecific association, it was shown as three types which were coincident with differential species and character species on the constancy table.

• The Korean Journal of Ecology
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• v.24 no.1
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• pp.9-18
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• 2001

The present study was undertaken to classify and describe the oak (Quercus spp). forests on Mts. Kaya, Bisul, Unmun and Kaji in southern Kyongpook Province, Korea by using a reciprocal averaging method (RA ordination) and the methodology of the ZM school of phytosociology. A temporary vegetation table was prepared by the RA ordination. The diagnostic species of the Quercus forests derived from the ordination were compared with the characteristic and differential species of the existing phytosociological vegetation units of the other mountainous areas of Korea. As a result, the forest vegetation was classified into the next vegetation units: Fagetea crenatae Miyawaki et al. 1968; Acero-Quercetalia mongolicae Song 1988; Rhododendro-Qurcion mongolicae Song 1988, 1. Stephanandra incisa-Quercus mongolica community 1-1 Sasa borealis subcommunity, 1-2 Disporum smilacinum subcommunity; Lespedezo-Quercion serratae Takeda et al. 1994, 2. Spodiopogon sibiricus-Quercus serrata community. The Rhododendro-Qurcion mongolicae and the Lespedezo-Quercion serratae correspond to the cool-temperate forests of the northern type and the southen type (Honda 1922), respectively, in the Korean Peninsula. Also some phytosociological problems in Korea were discussed here in detail from the floristic viewpoint in the present study.

• Journal of Korean Society of Forest Science
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• v.106 no.2
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• pp.150-168
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• 2017

This study was carried out to compare stand structure in Bihwajin basin Samcheok-si, Gangwon-do, Korea for ten years between 2003 and 2014, in which occurred the east coastal forest fire in 2000. Data were collected from 32 quadrates that followed by the analysis of vegetation classification according to plant sociology, importance value by Mclntosh and Curtise, species diversity and similarity index. In the result of vegetation classification, the vegetation unit decreased from 7 units to 4 units, and the number of species groups changed from 11 to 7. As a result of importance value (IV) changes, IV of Quercus mongolica, Q. serrata and Q. variabilis was increased by 6.8%, 5.2% and 2.9% in the order, respectively. However, that of Pinus densiflora was decreased by 2.8%. That of major planted species such as Castanea crenata, Chionanthus retusa, Prunus armeniaca var. ansu, Acer triflorum and Koelreuteria paniculata was reduced. As a result of species diversity, it was increased from 0.252 to 0.287 in tree layer, from 0.252 to 0.434 in subtree layer, and from 1.293 to 1.333 in shrub layer. But that in herb layer was decreased from 1.745 to 1.646. As a result of similarity index, it was 0.78, 0.65, 0.72 and 0.55 by layers that showed most difference in herb stratum. Considering the results, this study would be applied to the ecosystem diagnose and management of forest fire damaged area similar to the investigated area.

• Journal of Korean Society of Forest Science
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• v.88 no.3
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• pp.342-351
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• 1999

The forest vegetation developing on Mt. Inwang, an isolated forestland in Seoul, Korea was analyzed phytosociologically and its spatial distribution mapped out. Using the vegetation map, The characteristics of landscape structures in terms of the number and size of patches are discussed. Forest vegetation of the study area was classified into ten communities, ten groups, and eighty subgroups. Landscape element types were classified into secondary forests, relict communities, introduced plantations, and other elements including urbanized area. Pinus densiflora community, natural forest and Robinia pseudo-acacia community, plantation, formed matrix and some secondary forest elements, relict communities and the ether plantations of small size tended to distribute as small patches in such matrix. The number of patches per unit area in secondary forest elements was more than that in plantation elements. The result in patch size was vice versa. The vascular plant species richness of the landscape element types in Mt. Inwang was found to he positively related to their size. As the results of landscape ecological analyses, it was estimated that differentiation of patches recognized in community level would be related to human interference a and those in subordinate levels to natural process such as progression of succession.

• Journal of Korean Society of Forest Science
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• v.109 no.2
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• pp.124-135
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• 2020

Alder (Alnus japonica) forests are representative of the wetland in East Asia, including Korea. In the past, alder forests were relatively common in various habitats such as mountains, riversides, back marshes, and alluvial plains. However, this plant community has recently become rare due to increasingly arid habitats and the influence of various land uses. In this study, we identify the synecological characteristics of alder (A. japonica) forests distributed naturally in the mountainous wetlands of Korea and provide basic data for their systematic conservation and management in the future. Based on vegetation survey data collected from 66 alder forests, community types were classified using the methods of the Zürich-Montpellier School of Phytosociology and two-way indicator species analysis. There were eight community types: Styrax obassia, Weigela subsessilis-Fraxinus mandschurica, Spiraea fritschiana, Viola verecunda, Impatiens textori-Spiraea salicifolia, Glyceria leptolepis, Molinia japonica, and Lindera obtusiloba-Quercus acutissima. These community types constituted a vegetation unit hierarchy of two communities, four subcommunities, and eight variants. In addition, the ecological characteristics of each community type were compared (including total coverage per 100 square meter, importance value index, constancy class, life-form composition, diversity indices, community similarity coefficient, and indicator species).

• Korean Journal of Heritage: History & Science
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• v.55 no.3
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• pp.46-58
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• 2022

This study analyzed the documentation trend of garden components such as plants, infrastructure, unit facilities, and structures, based on 188 measurement drawings of 94 old houses in a report on the documentation of the national folklore cultural heritage. The findings are as follows. First, it was found that plants and structures continuously appeared as the subject of measurement drawings, while infrastructure was often omitted. It was confirmed that unit facilities, which are smaller than other components, were frequently excluded from the documentation subject as well due to frequent changes such as movement, loss, and expansion. Second, the level of expression in measurement drawings showed different aspects for each component. The unit facilities showed a large change over time with respect to the level of documentation, and the level of documentation was somewhat polarized, particularly toward the latter stage. This suggests that the level of documenting the drawings limited to specific facilities improved, but the overall level of drawings did not improve, such as a lack of diversification of expression techniques suitable for various unit facilities. On the other hand, it was confirmed that the level of documenting the drawings for plants, infrastructure and structures did not change to a significant degree, implying that no improvements were made to the expression of components. Third, as for the technique of detailed expression, in the case of plants, vegetation status was prepared without distinction of old or protected trees that have historical value. Above all, there was no record of the vegetation structure that could help grasp the vegetation landscape of the outer area. As for the infrastructure, there was no consistent expression technique to systematically convey topographic changes such as the height and slope of the land. In addition, since there was no subtype classification defined for unit facilities and structures, there was no subject or method of documentation. This study is meaningful in that it expanded the category of documentation, which has been concentrated on buildings in old houses, to gardens, and called attention to the need for documenting the gardens for the preservation and management of old houses as an integration of the building and outer area.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.3
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• pp.34-44
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• 2020

In order to suggest performance analysis directions of ecological components based on a vegetation-based LID system model, this study seeks to analyze the statistical significance between monitoring results by using SWMM computer simulation and rainfall and run-off simulation devices and provide basic data required for a preliminary system design. Also, the study aims to comprehensively review a vegetation-based LID system's soil, a vegetation model, and analysis plans, which were less addressed in previous studies, and suggest a performance quantification direction that could act as a substitute device-type LID system. After monitoring artificial rainfall for 40 minutes, the test group zone and the control group zone recorded maximum rainfall intensity of 142.91mm/hr. (n=3, sd=0.34) and 142.24mm/hr. (n=3, sd=0.90), respectively. Compared to a hyetograph, low rainfall intensity was re-produced in 10-minute and 50-minute sections, and high rainfall intensity was confirmed in 20-minute, 30-minute, and 40-minute sections. As for rainwater run-off delay effects, run-off intensity in the test group zone was reduced by 79.8% as it recorded 0.46mm/min at the 50-minute point when the run-off intensity was highest in the control group zone. In the case of computer simulation, run-off intensity in the test group zone was reduced by 99.1% as it recorded 0.05mm/min at the 50-minute point when the run-off intensity was highest. The maximum rainfall run-off intensity in the test group zone (Dv=30.35, NSE=0.36) recorded 0.77mm/min and 1.06mm/min in artificial rainfall monitoring and SWMM computer simulation, respectively, at the 70-minute point in both cases. Likewise, the control group zone (Dv=17.27, NSE=0.78) recorded 2.26mm/min and 2.38mm/min, respectively, at the 50-minutes point. Through statistical assessing the significance between the rainfall & run-off simulating systems and the SWMM computer simulations, this study was able to suggest a preliminary design direction for the rainwater run-off reduction performance of the LID system applied with single vegetation. Also, by comprehensively examining the LID system's soil and vegetation models, and analysis methods, this study was able to compile parameter quantification plans for vegetation and soil sectors that can be aligned with a preliminary design. However, physical variables were caused by the use of a single vegetation-based LID system, and follow-up studies are required on algorithms for calibrating the statistical significance between monitoring and computer simulation results.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.03a
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• pp.193-200
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• 1999

An experimental study is described in which a 305-mm-diameter instrumented drilled shaft was installed in a moderately expansive clay soil during the dry season and monitored over a period of about 18 months. The purpose of the study was In investigate the effects of seasonal moisture changes in the soil on the shear stresses imposed on the sides of the drilled shaft and movements of the shaft head. The soil in the vicinity of the test shaft was instrumented to measure suction and ground surface movement and the relation between suction, total stress and shear strength of the soil at the test site was determined through laboratory triaxial compression testing. Daily rainfall and temperatures were also monitored at the test site, the National Geotechnical Experimentation Site at the University of Houston, where control on surface grading and vegetation existed. Over the course of the study induced unit side shear values of up to 54 kPa were measured in the test shaft. A simple computational model was developed that related observed suction changes to unit side shear induced by the expansion of the soil through the use of the laboratory suction-total stress-shear strength relation.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.3
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• pp.17-25
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• 2006

To increase freeze-thaw resistance of porous concrete, this study examined physical properties of polymer by replacing paste used as a binding material with polymer, using unsaturated polyester and epoxy resin, and changing the mixing ratio of polymer. According to the result of this study, when the mixing ratio of resin paste to aggregates was 11 to 16%, voids volume was 33 to 37% and unit weight was about 1620 to 1720kg/$m^3$. In comparison with previous studies using cement paste, voids volume increased by about 7 to 16%, while unit weight decreased by about 100 to 300kg/$m^3$. Compressive strength was 90 to 155kg/$cm^2$ at the age of 7 days, which was 5-40kg/$cm^2$ bigger than porous concrete using cement paste. From a viewpoint of freeze-thaw resistance, it was identified that pluse velocity fell by 0.23km/sec, about 7% of the original velocity, when the cycle of freeze-thaw was repeated 300 times. In spite of 300 repetitions of the cycle, relative dynamic modulus of elasticity was more than 60%, which suggested that its freeze-thaw resistance was more excellent compared with the result that relative dynamic modulus of elasticity of porous concrete using cement paste was 60 % or less under the condition of 80 repetitions of freeze-thaw cycle.

• The Korean Journal of Ecology
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• v.23 no.2
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• pp.181-185
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• 2000

This study was carried out to see whether Gastrophysa viridula (Degeer) (Coleoptera : Chrysomelidae) could be used as a biological control agent for Rumex obtusifolius L., with human manipulation of the beetle population. The study was consisted of three experimental sets : Wet-Dry experiment (the wet weight Vs dry weight relationship of Rumex obtusifolius L.), Greenhouse feeding experiment, and Field experiment. There was a significant correlation between the total wet and dry weight of Rumex obtusifolius as follows : Total dry weight : -0.23542+ (0.17514${\times}$Total wet weight) ($R^2$=0.9317, p=0.047, T=16.927 (dF=21)). In the Greenhouse feeding experiment, the result was very promising. The relationship between the density unit of the beetles and the growth of the plant is given below (20 day) : Plant growth =105.8+(-34.4${\times}$Density unit) ($R^2$=0.76, p=0.13). A repeated introduction of the beetle population into the field vegetation of R. obtusifolius from April to October is suggested to see the beetle's grazing ability on the plant. This study shows that the potential grazing power of the beetle on Rumex obtusifolius was enough to defoliate the plants, but it was able to recover from its root reserves. The practical question remains as to whether repeated additions (by man) of the beetles to Rumex obtusifolius could eliminate them.