Song-Hyun Choi

A Study on the Potential Vegetation Recovery according to the Environment and Type of Tunnel Entrance and Exit

The purpose of this study is to classify, evaluate and grade the existing highway tunnels to increase landscape and natural statistics keeping the structural safety about tunnel gates area and induce the ones that will be constructed in the future by drawing the improvements and restoring the techniques as an environment-friendly. To examine the types of tunnel gate area, total 54 tunnels were investigated by selecting Gyeongbu Expressway, Yeongdong Expressway, and Jungang Expressway. Tunnel entrances and exit ports were classified as a Wall-closed type and Protruding type, which is based on tunnel gate type. Vegetation Landscape types were classified as Multilayer-Same as the surrounding landscape_(MS), Multilayer-Difference of surrounding landscape_(MD), Single layer-Same as the surrounding landscape_(SS), Single layer-Difference of surrounding landscape_(SD), and a Desolate type which based on vegetation layers and environment-friendly. Potential vegetation recovery was identified based on the structural stability and revegetation potential of the tunnel. The factors include the structural stability of the slope height and slope gradient were selected. Revegetation potential was identified as a growth potential. This factor was used in the step to classify vegetation recovery potential of a tunnel. The result, which investigated the types of tunnel entrances and exit parts has found that the most typical in 33 places was a Wall closed type with 61.1% of the total ones. The case of vegetation landscape types was created but different from the ones surrounding it with 85.2% of the total ones. It is judged that the currently constructed vegetation of tunnel entrance and exit parts had put convenience on the safety and management before landscape consideration. In addition, tunnel entrance and exit parts with excellent potential for vegetation recovery were all Protruding type. In addition, it is judged that slope stability can easily obtain growth. Therefore, entrance and exist of the highway tunnels, which will be constructed in the future, should reflect location and the result of the natural and ecological survey in design by performing it in advance and their types, which minimize the damage area range, should be applied to the local characteristics suitably. In addition, the ecologically healthy tunnel construction should be done by introducing active vegetation recovery techniques based on its safety.

A Study about the Presumed Economic Value of Miscanthus Landscape Conservation - Miscanthus Colonies in Youngnam Province -

To detail a picture of the economic value of Miscanthus landscape conservation in terms of cultural services aspects of Ecosystem Services, Sunghaksan(Mt.), Hwawangsan(Mt.) and Jaeyaksan(Mt.), which are known for their Miscanthus colonies, were chosen as survey sites. After examining the willingness to pay for the value of Miscanthus landscape conservation by targeting of visitors each study area, the economic value of Miscanthus landscape conservation per capita aspects was evaluated using Contingent Valuation Methods(CVM) from the collected willingness to pay for economic value of Miscanthus scenery by site. After using the target Chi-square test to analyze the differences among each site, the correlation between specific variables was investigated. Willingness to pay for the Miscanthus landscape conservation was found to increase as the respondents’ income became higher. The more environmental conservation efforts were being made in their daily life, the higher willingness to pay was for Miscanthus landscape conservation. Likewise in other studies, the higher the bid was, the less willingness to pay was. The per capita assessment of the Miscanthus landscape value of the logit models in the dual estimated using the factor extracted with each of the injected variable bounds was estimated for Seunghaksan (₩38,277), Hwawangsan(₩38,648), and Jaeyaksan(₩48,891). The average of the three sites was estimated to be ₩38,679. Assessment of the economic value of these Miscanthus landscape sites saw high willingness to pay by visitors when compared to the current market price inflation, such as watching movies or amusement park admission, which could mean that visitors recognize the value of ecosystem services from nature in evaluating the Miscanthus landscape.

A Study of Establishment Ratio of Native Tree Transplant

To fulfill the need for reuse indigenous tree to mitigate the elimination of nature forests due to road construction, one representative method for this reuse is to transplant them and re-establish in similar conditions. In order to investigate the transplant and establishment of indigenous tree, a correlation and regression analysis was conducted by species and tree size. Data were collected for 6 years(2008~2013) in 7 construction sites in cooperation with the Korea Expressway Corporation. Regarding the transplanted indigenous trees status, the success rate of transplant was 15,519(69%) of 22,521. The tree most transplanted was Pinus densiflora(15,562), followed by Quercus spp.(6,156), Prunus sargentii(235), and P. thunbergii(154). P. densiflora and P. thunbergii belong to the conifer group while Quercus spp., Prunus sargentii belong to the broadleaf group. As a result of a contrast test, the conifer group had a significantly lower success rate of transplant than the broadleaf group. In the relation of root collar diameter and success rate of transplant, there was the tendency that the larger the root collar diameter, the lower the success rate of transplant. This study demonstrated that there is a strong negative correlation between the two factors(r=-0.730, p>0.000). The predicted regression equation of the success rate of transplant was Y=-0.811X+88.627(X: root collar diameter, Y: success rate of transplant) and the R value for the linear equation was 0.532.

Classification Type of Vascular Plants in Yeohangsan, Muhaksan and Palyongsan, Masan

The vascular plants in Yeohangsan, Muhaksan and Palyongsan were listed 373 taxa; 87 families, 222 genera, 284 species, 3 subspecies, 71 varieties and 15 forms. The flora in the Yeohangsan were listed 267 taxa, Muhaksan were listed 199 taxa and Palyongsan were listed 163 taxa. Divided into 373 taxa; woody plants were 142 taxa (38.1%) and herbaceous plants were 231 taxa (61.9%). Based on the list of rare plants (IUCN) by the Korea Forest Service and Korea National Arboretum, 3 taxa (Wikstroemia ganpi, Tricyrtis macropoda, etc.). Based on the list of Korean endemic plants, 10 taxa (Philadelphus schrenkii var. schrenkii, Indigofera koreana, Lespedeza maritima, Stewartia pseudo-camellia, Weigela subsessilis, Hosta minor, etc.). Specific plants by floral region were total 34 taxa (9.1% of all 373 taxa of vascular plants); 2 taxa (Dumasia truncata, etc.) in class IV, 4 taxa (Rhus succedanea, Stewartia pseudo-camellia, Salvia japonica, etc.) in class III, 3 taxa (Viola orientalis, Cymopterus melanotilingia, Teucrium veronicoides) in class II, 25 taxa (Dryopteris erythrosora, Betula schmidtii, Quercus variabilis, Aphananthe aspera, Morus cathayana, Nanocnide japonica, Clematis patens, Rhynchosia acuminatifolia, Euonymus japonicus, Meliosma oldhamii, Cayratia japonica, Ardisia japonica, Ligustrum japonicum var. japonicum, Trigonotis icumae, Microstegium japonicum, Arisaema ringens, Polygonatum falcatum, etc.) in class I. Based on the list of naturalized plants, 20 taxa (Rumex crispus, Chenopodium album var. album, Amaranthus lividus, Phytolacca americana, Lepidium apetalum, Trifolium repens, Ailanthus altissima for. altissima, Oenothera biennis, Galinsoga ciliata, Bromus unioloides, etc.) and naturalization rate was 5.4% of all 373 taxa of vascular plants.