• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.6151-6158
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• 2012

By the activation of environment-friendly river works, application of vegetation mats is increasing, however, evaluation techniques for hydraulic stability of vegetation mats are not presented. This study is conducted to develop the objective test method for vegetation mats. Two kind of vegetation mats are tested by the real scale experiments, and hydraulic quantities are measured and analyzed to evaluate acting shear stresses. Roughness and shear stress are evaluated by 1 D non-uniform model. After each tests, changes in mat surfaces and sub-soil are evaluated, and from these evaluation, 3 types of mat surface damages and 2 types of sub-soil damages are presented. In the study, the case in which some damages in mat surface don't cause loss of sub-soil, is presented to be in the stable condition. Appling this stable condition and acting shear stresses, permissible shear stresses of vegetation mats are evaluated, and the results show that the reinforced mat with wire netting has more permissible shear stress.

• Korean Journal of Environmental Biology
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• v.34 no.1
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• pp.41-47
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• 2016

The phytosociological study was carried out to investigate the structural characteristics of coastal vegetaion in South Korea. The vegetation data of total 102 sites were analyzed by the $Z{\ddot{u}}rich$-Montpellier school's method. Eleven community of coastal vegetation were recognized : Vitex rotundifolia-Rosa wichuraiana community, Calystegia soldanella community, Carex kobomugi-Elymus mollis community, Zoysia sinica community, Suaeda maritima community, Suaeda australis community, Suaeda glauca-Atriplex gmelinii community, Suaeda japonica community, Phragmites communis community and Calamagrostis epigeios community. Principal componant analysis (PCA) showed the similar result with phytosoiological classification.

• The Korean Journal of Ecology
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• v.11 no.4
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• pp.175-192
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• 1988

The coastal vegetation of the southwestern coast of Korea was surveyed by the Braun-Blnquet's phytosociological sKDICe and its soil properties were also determined. Comparing with the coastal vegetation of Korea, Japan and Europe, the vegetation of this area could be classified into as follows; A. Thero-Salicornietea R. Tx. 1954(Salicor-nietum herbaceae assoc. nov.). B. Thero-Suaedetea Rivas Martwez 1979 (Suaedetum japonicae Miyawaki et Ohba 1966, Suaeda maritima commuity, Atriplici-Suaedetum maritimi Miyawaki et Ohba 1965, Suaeda asparagoided community) C. Asteretea tripolium Westhoff et Beeftink 1962 (Zoysietum sinice Ohba, Miyawaki et Tx. 1973, Limonietum tetragoni Miyawaki et Ohba 1969, Artemisietum scopariae assoc. nov., Aster tripolium community, Atriplex, gmelini community) D. Phragmitetea Tx. et Prsg. 1942 (Triglochietum maritimae assoc. nov., Carcetum scabrifoliae Miyawaki et Ohba 1969, phragmites communis community, Pyaceluretum latifolii Miyawaki et Okuda 1972, Scirpus fluviatilis community) E. Salsoletea komarovil Ohba, Miyawaki et Tx. 1973(Salsola komarovi community) F. Glehnietea littoralis ohba, Miyawaki et Tx. 1973(Caricetum pumilae assoc. nov., Meserschmidia sibirica community, Lysimachia mauri-tiana community Ishaemum anthephoroides community, Elymus mollis commuity, carex kobomugi community, Ixeris repens community) G. Viticetea rotundifoliae Ohba, Miyawaki et Tx. 1973 (Imperato cylindricae-Viticetum rotundifoliae ohba, Miyawaki ex Tx. 1973) and Opuntia ficus-indica var. saboten community. Among the soil properties, water potential seems to be one fo the most important factor on the distribution of the coastal plant community and it might be highly affected by water content in sand and salinity in low marsh.

• The Korean Journal of Ecology
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• v.18 no.3
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• pp.307-321
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• 1995

Division of ecoregions having respective functions was attempted through quantitative and qualitative analysis on vegetation diversity, and heterogeneity and on soil environment of the study sites. Field research was carried out in a square of 81 ㎢ around Andongpo (126°38'E, 37°30'N), Kimpo-gun, Kyonggi provice. Conventional methods applied are as follows: classical syntaxonomy by the Zurich-Montpellier School, interpolation method to determine the degree of diversity, heterogeneity and distribution pattern of vegetation, and correlation analysis between soil properties and plant communities. 41 plant communities were identified and composed of 6 forests, 4 mantle and 31 herb communities including 6 saltmarsh plant communities. In a mesh, number of plant communities was highly correlated to the number of species. The highest number of plant community and species was 25 communities·km-2·mesh-1 and 381 species· km-2·mesh-1 ,and the highest value of vegetation heterogeneity was 28.1 species· community-1·mesh-1. Their lowest numbers were 4 communities·km-2·mesh-1. and 28 species·km-2·mesh-1. and 7 species·community-1·mesh-1, respectively. Contour map on vegetation diversity and heterogeneity enabled us to establish two regions; coastal and inland vegetation. Isoline 〔150〕,〔10〕and〔10〕and〔15〕on the species diversity, the community diversity and the vegetation heterogeneity, respectively, were regarded as ecolines in the study area. Cl- content was recognized as the most important factor from correlation analysis between soil properties. Ordination of sites indicated that the study area be divided into two edaphic types: inland and coastal habitats. It was considered that the extent of desalinization in soil played a major role in determining the species composition in the reclamed area. By matching edaphic division of habitats with division of vegetation structures, designation of ecoregion was endorsed. The approach of current study was suggested as an effective tool to implement an assessment of the vegetation dynamics by the disparity of natural environment and anthropogenic interferences.

• Journal of Ocean Engineering and Technology
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• v.14 no.3
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• pp.46-54
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• 2000

Three dimensional numerical experiments that included the land-use transformation by the large scale reclamation were used to investigate the mesoscale air flow over the coastal regions. In this paper the surface temperature of the inland was determined through the surface heat budget consideration with inclusion of a layer of vegetation. The vertical diffusion coefficients of momentum, heat and specific humidity in the constant flux layer were taken from the Mellor and Yamada(1975). It has shown that the resulting model is able to reproduce the air circulation in coastal regions, and the simulated characteristics agree with the known properties of this circulation. A series of numerical experiments were then carried out to investigate the diurnal response of the air flow to various types of surface inhomogeneities.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.5956-5963
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• 2013

By the activation of environment-friendly river works, application of vegetation mats is increasing, however, evaluation techniques for hydraulic stability of vegetation mats are not presented. This study is conducted to develop the objective test method for vegetation mats. Two kind of vegetation mats are tested by the real scale experiments, and hydraulic quantities are measured and analyzed to evaluate acting shear stresses. To evaluate soil loss, Terrestrial 3D LiDAR measurement is conducted and soil loss index are calculated from changes of bed elevation. Quantified evaluation for permissible shear stresses is conducted by graphical method for acting shear stresses and soil loss index. By the results of precision survey, changes of sub soil are limited to local range in stable cases and relatively large changes of sub soil which is similar to natural river bed are detected in unstable cases. From the study, evaluation of permissible shear stresses by ASTM D 6040 is avaliable in the failure mechanism and failure criteria by soil loss index.

• The Korean Journal of Ecology
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• v.26 no.3
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• pp.103-108
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• 2003

This study examined the coastal sand dune vegetation before and after the construction of an embankment on Anmado Island in order to compare vegetation in relation to the development of islands. A total of 24 species distributed on the sand dunes. 18 species were found to be in common before and after the construction of the embankment, which included Vitex rotundifolia, Imperata cylindrica var. koenigii, Zoysia sinica, etc. The species which were not found in this survey included Rumex japonicus, Setaria viridis, Portulaca oleracea, Artemisia japonica, Poiygonum aviculare, etc, and new species included Arena fatua, Carex boottiana, Lycium chinense, Leonurus sibiricus, Torilis japonica, Solanum carolinense, etc. The washing away of sand brought about the changes in habitat and the increase in naturalized plants, which included Oenothera odorata, Lepidium apetalum, Bidens bipinnata, Erigeron canadensis, Datura stramonium, Xanthium strumarium, Arena fatua, Solanum carolinense etc. In addition, the disturbance to this habitat led to the changes in vegetation. The main plant communities in the surveyed site were classified as Vitex rotundifolia-Imperata cylindrica var. koenigil community, Zoysia sinica-Calystegia soldanella community and Messerschmidia sibirica community. The sand dune vegetation on Anmado Island changed with regard to the community and the composition of species after the construction of the embankment, due to the sand being severely eroded. While Vitex rotundifolia community and Commelina communis community were found before the construction of the embankment, they were replaced by Vitex rotundifolia-Imperata cylindrica var. koenigii community, Zoysia sinica-Calystegia soldanella community and Messerschmidia sibirica community, after the construction of the embankment.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.25 no.6
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• pp.25-33
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• 2022

In this study, a monitoring method using high-resolution images acquired by unmanned aerial vehicles and deep learning algorithms was proposed for the management of the Sinduri coastal sand dunes. Class classification was done using U-net, a semantic division method. The classification target classified 3 types of sand dune vegetation into 4 classes, and the model was trained and tested with a total of 320 training images and 48 test images. Ignored label was applied to improve the performance of the model, and then evaluated by applying two loss functions, CE Loss and BCE Loss. As a result of the evaluation, when CE Loss was applied, the value of mIoU for each class was the highest, but it can be judged that the performance of BCE Loss is better considering the time efficiency consumed in learning. It is meaningful as a pilot application of unmanned aerial vehicles and deep learning as a method to monitor and manage sand dune vegetation. The possibility of using the deep learning image analysis technology to monitor sand dune vegetation has been confirmed, and it is expected that the proposed method can be used not only in sand dune vegetation but also in various fields such as forests and grasslands.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.1
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• pp.89-104
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• 2011

This study was carried out to the development of ecological planting model to make up of coastal windbreak forest on the Suncheon-bay in Sucheon-si, Korea. Make up of coastal windbreak forest in this site was needed for appropriate bioresource, biodiversity and ecological structure, and for conservation of the eco-tour resource and protection of human life and property by the unforeseen disaster from the coast. Based on the plant-social principle, the planting model of windbreak forest was developed to facilitate growth of trees, considering planting locations. The ecological planting model for the coastal windbreak was composed of warm temperate evergreen and windbreak forest which is spreading around the inland area in Korea. The horizontal forest style was composed of forest edge community and inner forest community, and the vertical forest style was composed of upper, middle, low and ground planting class. The target of the present model was quasi-natural forest, and the species of tree were selected based on the adaptability to surroundings depending on a goal to create a forest and forest style. To achieve both functions of wind break forest and visual effect in short period of time, small trees and seedlings were planted with high-density of 40,000/ha in an expectation of easy natural maintenance in the future. The significance of the present study is a suggestion for a guideline to create ecological coastal windbreak forest in the Suncheon-bay in which the harmony of human life and the ecological conservation is of great importance. Also, the ecological coastal windbreak forest model should be developed further through the long term monitoring after construction of forest.

• Korean Journal of Environment and Ecology
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• v.23 no.6
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• pp.499-505
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• 2009

This study was carried out to investigate and evaluate the vegetations in the coastal dunes in the vicinity of swimming beaches on the East Sea, South Korea, and the vegetations that were investigated are as follows: Carex pumila community, Cynodon dactylon community, Zoysia macrostachya community, Rosa rugosa community, Vitex rotundifolia community and Carex kobomugi typical community. Some of these vegetations, such as Carex kobomugi, Calystegia soldanella, Ixeris repens, Elymus mollis, Lathyrus japonica, and Glehnia littoralis were found to be differential species which belongs to Caricion kobomugi of Glehnietea littoralis. It was also discovered that Vitex rotundifolia community was the most heterogeneous among vegetation communities of the coastal dunes surrounding swimming beaches, and Zoysia macrostachya community was most closely linked to the typical coastal dune vegetation community. Finally, Rosa rugosa community and Vitex rotundifolia community seemed to have formed near the hinterland of coastal dunes and swimming beaches respectively because of certain unnatural disturbances such as construction of buildings and facilities or natural disasters.