• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.5
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• pp.47-57
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• 2016

In the recent years, the incidence of abandoned concrete roads have been increasing rapidly due to road improvements and facilities route construction, these abandoned expressway and unused roads are scattered throughout the country but the management system is not clear, they does not be an effectively managed because there is no maintenance cost. In response to these social concern and expectation, the Korea Expressway Corporation that is management authority of the expressway is developing policy initiatives and various projects to restore the closed road to ecological for eco-friendly projects of the existing expressway. And as part of these projects, Hwanggan IC unmanaged abandoned concrete roads restoration project was done and it was conducting monitoring for ecological restoration that is not one-off but sustainable. After test construction over seven years at the time, test construction of four ways enforced but the boundaries have become blurred over time. And Pinus koraiensis, Callicarpa dichotoma and Sorbaria stellipilla var. typica planted in the site are dominating, else Amorpha fruticosa and Indigofera pseudotinctoria sowed are dominating. Invasive species is that Robinia pseudoacacia was growing in the colony. Over monitoring result time, the vegetation was taking root and the ecosystem was being restore. But the disturbance of vegetation happens due to planting of tree species that doesn't fit in the restoration area and advent of ecosystem Disturbing Species. The study will be providing a basic data that identify change of plant environment by monitoring of the site and soil environment during June to November 2016 and secure an objective evaluation data by analyzing the effects of ecological restoration for revegetation test bed evaluation for ecological restoration of expressway in ecological restoration construction in later.

• Journal of Korean Society of Forest Science
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• v.103 no.2
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• pp.248-257
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• 2014

The objectives of this study were to identify the root plate dimension of wind-uprooted trees and to analyze the relationship among wind direction, aboveground and belowground properties of the trees. The root plates of 77 Japanese larches (Larix kaempferi) and 24 Korean pines (Pinus koraiensis), which were uprooted by a typhoon in 2012, in the Taehwa Experimental Forest of Seoul National University, Korea, were investigated. The results showed the root plate shape could be assumed to be an oval or a circle in above view, and half an ellipse in side view, respectively. Also, the number and surface area of individual roots in root plates were greater in uprooting direction than in non-uprooting direction. The results of correlation analyses between aboveground and belowground properties indicated DBH had more significant correlation with belowground properties than tree height. Finally, simple linear relationships were derived for significantly correlated tree aboveground and belowground properties.

• Journal of the Korean Wood Science and Technology
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• v.45 no.6
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• pp.728-736
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• 2017

In this study, the bending behavior of cross-laminated timber (CLT) connected by nails were investigated. Especially, the load-carrying capacity of the nail-jointed CLT under out-of-plane bending was predicted by the lateral resistance of the used nails. Three-layer nail-jointed CLT specimens and a nail connection were manufactured by 30 mm (thickness) ${\times}$ 100 mm (width) domestic species (Pinus koraiensis) laminas and Ø$3.15{\times}82mm$ nails using a nail-gun. Shear test for evaluating the nail lateral resistance and bending test for evaluating the load-carrying capacity of the nail-jointed CLT under out-of-plane bending were carried out. As a result, two lateral resistance of the used nail, the 5% fastener offset value and the maximum value, were 913 N and 1,534 N, respectively. The predicted load-carrying capacity of the nail-jointed CLT by the 5% offset nail lateral resistance was similar to the yield points on the actual load-displacement curve of the nail-jointed CLT specimens. Meanwhile, the nail-jointed CLT specimens were not failed until the tension failure of the bottom laminas occurred beyond the maximum lateral resistance of the nails. Thus, the measured maximum load carrying capacities of the nail-jointed CLT specimens, approximately 12,865 N, were higher than the predicted values, 7,986 N, by the maximum nail lateral resistance. This indicates that the predicted load-carrying capacity can be used for designing a structural unit such as floor, wall and roof able to support vertical loads in a viewpoint of predicting the actual capacities more safely.

• Journal of Plant Biology
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• v.17 no.4
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• pp.23-30
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• 1974

The relations of the growth responses of plants, i.e. 4 species of crops, 12 species of roadside trees and 5 species of horticultural plants to cadmium (Cd) to which added soil were studied in pot culture. Growth in dry weight of corn, soybean, barley and wheat plant were decreased with increase of Cd concentration. Damage of corn plant caused by Cd treatment was more or less recovered when it was grown in soil with calcium, but that of other three crops was not recovered when it was with calcium. Although crop plants used here absorbed small amount of Cd through root, Cd content in the shoot was directly proportionate to the concentration of Cd treated to soil. Additions of calcium and sulfur to soil were effectively to change of soil pH, and only of calcium increased exchangeable calcium and cation exchange capacity of its soil. The chlorosis on leaves caused by Cd treatment was observed in 2 species such as Euonymus japonica and Rhododendron yedoense out of 5 species of the horticultural plants, especially at 50ppm of Cd concentration, Euonymus japonica occurred symptoms of chlorosis and difoliation, and at the higher concentration than that the symtoms were sever more and more. At 200 ppm of Cd feeble damage was observed in Pinus koraiensis and Ginkgo biloba but severe chlorosis observed in Robinia pseudoacacia and Sabina chinensis, Buxus koreana, Abies holophylla and Platanus orientalis. Nevertheless those plants had serious damage at 200 ppm of Cd, such symptom was weakened by adding calcium to soil with Cd. There were many Cd tolerant species out of the plants used in thies xperiment, such as Crassula falcata, Chrysanthemum morfolium, Hibiscus syriacus, Ligustrum ovalifolium, Liriodendron tulipeferia, Lespedeza crytobotrys.

• Journal of Korean Society of Forest Science
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• v.76 no.3
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• pp.218-229
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• 1987

This study was carried out to investigate all the parts' weight growth under the different light intensity and root-cutting. As results : ${\cdot}$ Fresh and dry weight of leaf, shoot, root and seedling treated under 63% R.L.I showed the largest growth. ${\cdot}$ The largest growth in fresh and dry weight of shoot arid seedling appeared at 1/4 root cutting plot. ${\cdot}$ The value of T/R ratio was increased in low light intensity and high root-cutting. ${\cdot}$ The simple nonlinear relationship between light intensity, root-cutting and T/R ratio was recognized, respectively.

• Korean Journal of Ecology and Environment
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• v.47 no.4
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• pp.337-341
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• 2014

The changes in the area and standing crop of forests and the understory vegetation structure of various plantations were investigated by literature survey to predict the changes in the structure of forest ecosystems of the Korean Peninsula in the future. The greater part of forest was severely destroyed in 1950's in the Korean Peninsula. The forest standing crop has been dramatically increasing since the nationwide plantation was actively performed in 1970's and 1980's in the Republic of Korea. The area of forest was incessantly decreased at the rate of $5,500ha\;yr^{-1}$. The results of regression analysis on the changes in forest standing crop of the Republic of Korea showed that the forest might approach to the maturity stage in around 2150. It was predicted that the potential natural vegetation of Quercus mongorica, Fraxinus rhynchophyllus, Prunus sargentii, etc. would establish in the plantations of Larix leptolepsis, Pinus koraiensis and Robinia pseudoacacia in the future.

• Korean Journal of Environment and Ecology
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• v.15 no.2
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• pp.118-124
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• 2001

본 연구의 목적은 도식에 식재된 두 침엽수조인 소나무와 잣나무 단목의 연간 $CO_2$, $SO_2$, $NO_2$ 흡수 및 $O_2$ 생산을 계량화하는 것이다. 자연환경 조건하에서 운반형 적외선가스분석기로 연간 $CO_2$교환율을 측정하여 $CO_2$흡수 및 $O_2$ 생산량을 그리고 $CO_2$와 SO$_2$EH는 $NO_2$간 흡수속도비를 적용하여 $SO_2$ 및 $NO_2$흡수량을 각각 산정하였다. 흉고직경을 독립변수로 단목의 생장에 다른 연간 $CO_2$흡수 및 대기 정화량을 추정하는 활용 용이한 방정식을 유도하였다. 연구대상 수목 중, 흉고직경 20cm인 잣나무는 연간 양 35kg의 $CO_2$, 11g의 $SO_2$, 19g의 $NO_2$를 각각 흡수하였고 25kg의 $O_2$를 생산하였다. 동일 직경의 소나무는 유도한 방정식을 적용하면, 연간 약 30kg의 $CO_2$, 9g의$ SO_2$, 15g의 $NO_2$를 각각 흡수하였고 22kg의 $O_2$를 생산하였다. 생상기간 중 단위엽면적당 $CO_2$흡수량은 잣나무가 소나무보다 적었으나, 단목의 연간 $CO_2$흡수 및 대기정화량은 총엽면적의 차이로 잣나무가 동일 직경의 소나무보다 많았다. 본 연구결과는 도시 침엽수의 연간 대기정화 가치를 용이하게 계량화학고 도시공간내 수목식재의 환경적 중요성을 홍보하는데 활용될 수 있다.

• Korean journal of applied entomology
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• v.34 no.2
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• pp.120-126
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• 1995

This study investigated the soil oribatid mite community at planatations of the Korean white pine, planted in different years. The soil samples $(10\times10\times5cm)$ were taken monthly from Jun 1988 to July 1989, and soil microarthropods in th sample were extracted using the Tullgren funnel for 72 hors. The diversity indices decreased at the older plantation sites with the maximum point in January and the minimum in September. The richness indices showed the maximum point in June and the minimum in may. The dominance indices increased at the older plantation and showed the maximum point in April, May, the minimum in January. The indices of aggregation of Oribatid mites species showed concentrated distribution in the average 1.9. The older plantation, the more indices increase. The seasonal variation of th indices tended to be greatest in April, August and at lowest in January. The richness indices was positively correlated with shannon-wiener, evenness indices. The dominance, aggregation indices was negatively correlated with shannon, evenness, richness indices.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.1
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• pp.103-113
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• 2015

Korean pines(Pinus koraiensis) are one of the major plantation species in the Republic of Korea and their natural habitats range from Japan and China to Siberia. The seed of Korean pines, pine nuts, are well know for good food reserves. Due to the global changes which drive the Korean peninsula into the semi-tropical climate, current plantations and natural habitats of Korean pines are faced with the change in the environmental conditions to some extent. To anticipate suitable sites for Korean pines in the future, the location of Korean pines were extracted from the 'Map of suitable trees on a site' that provides the map of suitable trees on a site considering tree species for timber and special uses, and then MaxEnt modelling was used for generating a prediction map on the basis of statistical analysis. As a result, the order of predicted suitable sites were Kangwon-do, Kyungsangbuk-do and Chungcheongbuk-do provinces and sites with high elevation within those provinces were considered most suitable in common. The prediction map of suitable sites for Korean pines presented that suitable sites in the future decreased by 72.2% by 2050's and almost disappeared with a decrease of 92.1% by 2070's on a nationwide scale. In relation to the major production regions of pine nuts in South Korea - Gapyung gun and Yangpyung gun, Kyunggi province and Hongcheon gun, Kangwon province, suitable sites within their areas were predicted to increase by 2050's but become extinct in South Korea by 2070's. To establish a long-term countermeasures against the improvement on forest productivity quality in terms of managing national food security, the result from this study can be considered as a firm basis of predicting plantation suitability. Also, it can be used to predict the changes in supply of forest products and thereby market values in accordance with climate change scenarios.

• Journal of the Korean Wood Science and Technology
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• v.46 no.5
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• pp.471-485
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• 2018

Post-heat treatment experiments were carried out for complete dimensional stabilization of thermally compressed wood (Pinus koraiensis). An absorption test was carried out to evaluate the dimensional stability. The specific gravity increased from 0.43 to 0.79 by thermal compression at a compression ratio of 50% thickness. Through the post-heat treatment of compressed wood, the water absorption and thickness swelling decreased with increasing the heat treatment temperature and time. In the case of the thickness recovery rate, when the heat treatment was performed for 24 hours at $120^{\circ}C$, $140^{\circ}C$ and $160^{\circ}C$, the thickness recovery was less than 1%. Therefore, it can be confirmed that the method of dimensional stabilization method of the thermal compression wood can be carried out very effectively through post heat treatment process.