• Journal of Climate Change Research
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• v.8 no.4
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• pp.393-399
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• 2017

According to the United Nations Framework Convention on Climate Change (UNFCCC), all parties have to submit the national GHG inventory report. Estimating carbon stocks and changes in Land Use, Land-Use Changes and Forestry (LULUCF) needs an activity data and emission factors. So this study was conducted to develop carbon emission factor for Robinia pseudoacacia L., Betula platyphylla var. japonica, and Liriodendron tulipifera. As a result, the basic wood density ($g/cm_3$) was 0.64 for R. pseudoacacia, 0.55 for B. platyphylla, and 0.46 for L. tulipifera. Biomass expansion factor was 1.47 for R. pseudoacacia, 1.30 for B. platyphylla, and 1.24 for L. tulipifera. Root to shoot ratio was 0.48 for R. pseudoacacia, 0.29 for B. platyphylla, and 0.23 for L. tulipifera. Uncertainty of estimated emission factors on three species ranged from 3.39% to 27.43% within recommended value (30%) by IPCC. We calculated carbon stock and change using these emission factors. Three species stored carbon in forest and net $CO_2$ removal was $1,255,398\;t\;CO_2/yr$ during 5 years. So we concluded that our result could be used as emission factors for national GHG inventory report on forest sector.

• Journal of the Korean Wood Science and Technology
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• v.28 no.4
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• pp.29-40
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• 2000

Highly purified Cerrena unicolor laccase (benzenediol:oxygen oxidoreductase, EC 1.10.3.2) caused the demethoxylation of milled wood lignin and several lignin related substances. The constitutive form of the enzyme produced extracellularly by C. unicolor fermenter culture was isolated and purified by ion-exchange chromatography on the DEAE-Toyopearl column and by affinity chromatography on a ConA-Sepharose and Syringyl-AH-Sepharose 4B columns. The enzyme was further immobilized on functionalized porous glass (CPG) and keratin coated CPG. The demethylating activity was monitored both by estimation of released methanol and by detection of the level of methoxyl groups (also in some water miscible solvents) after incubation of lignin materials with laccase preparations (free and immobilized). The effects of the incubation time and temperature on the demethoxylating activity of immobilized laccase preparations were also studied.

• Journal of Ecology and Environment
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• v.34 no.3
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• pp.315-322
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• 2011

We investigated the effect of Pb uptake by Pinus densiflora and the Pb fraction in forest soil. We also investigated the change in soil physicochemical characteristics, microbial activity, and root exudates of Pinus densiflora in Pb-contaminated soils. Three-year-old pine seedlings were exposed to 500 mg/kg Pb for 12 months. The metal fractions were measured using sequential extraction procedures. Additionally, factors that affect solubility (three soil enzyme activities and amino acids of root exudate compounds) were also determined. The results showed that Pb contamination significantly decreased enzyme activities due to soil characteristics. In addition, organic matter, nitrate content, and Pb concentration were time dependent. The results indicate that changes in the Pb fraction affected Pb uptake by pine trees due to an increase in the exchangeable Pb fraction. The concentrations of organic acids were higher in Pb-spiked soil than those in control soil. Higher rhizosphere concentrations of oxalic acid resulted in increased Pb uptake from the soil. These results suggest that pine trees can change soil properties using root exudates due to differences in the metal fraction.

• Korean Journal of Environment and Ecology
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• v.33 no.6
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• pp.748-757
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• 2019

This study was intended to investigate the effects of forest therapy programs using school forest on the emotional stability and positive thinking of university students. The subjects were divided into an experimental group and a controlled group, and the number of subjects in each group was 35 and 25, respectively. The forest therapy program was conducted once a week from 4 September to 12 December in 2018 for a total of 8 sessions, and each session lasted two hours (120 minutes). The subjects were examined in the emotional state and positive thinking before and after the forest therapy program. To determine the difference in emotional stability and positive thinking before and after the program, I conducted a paired t-test and analyzed the data with the SPSS 21.0 program. The results indicated that students who participated in the program showed a significant increase in the stabilize emotional state and positive thinking. This study shows that forest therapy programs using school forests have an effect on students' emotions and positive thinking. Thus, it is necessary to promote the forest therapy program as an alternative activity for the treatment and prevention of mental health of university students.

• Korean Journal of Environment and Ecology
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• v.35 no.4
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• pp.424-434
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• 2021

People who face retirement in aging society experience changes in resilience and psychological depression. As the baby boomer generation, which has played a central role in Korea's economic and social sectors, begins retiring, interest in their post-retirement lives has also increased. Thus, this study investigates the effects of a forest healing program using forest healing factors of ecological forests on the resilience and depression of baby-boomer retirees. This experiment divided 58 subjects in the baby boomer generation into three groups and examined differences among the groups. The result showed that the subjects in the forest healing program group (FHPG) had a very significant increase in resilience and a statistically significant decrease in depression compared to those in the forest healing program non-participation group (FHNG) and the daily life group (DLG). Therefore, it can be said participating in the forest healing program is more effective for retirees than voluntary forest activities. The results of this study can be used as basic data for research on the resilience and depression of retirees.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.6 s.119
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• pp.78-86
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• 2007

Research into the use of recreation forest accommodations, the main facilities in these forests, and user satisfaction with them has been carried out for recreation forests in the suburbs of Daegusi and Gyongsangbukdo. This study aimed at providing background material to support the increasing demand to improve the facilities of recreation forests and to educate recreation forest staff about how to provide better service. User satisfaction with recreation forests as determined through regression analysis was affected by the following factors in this order: indoor recreation, the indoor space, outdoor recreation, time satisfaction factor, and activity opportunities. The level of satisfaction is affected by the force of factors above. The order of effective offerings of accommodations is presented according to the results.

• Journal of Forest and Environmental Science
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• v.34 no.3
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• pp.258-261
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• 2018

Drought alters soil microorganisms; however, it is still not clear how soil microbes respond to severe drought conditions. In this study, the responses of soil bacterial community to experimental drought in a coniferous stand were examined. Six $6m{\times}6m$ plots with three replicates of control and drought treatments were delimited. PCR amplification and Illumina sequencing were conducted for cluster analysis of soil bacterial community and species richness and species diversity was analyzed. Along the 393 days of simulated drought from July 2016 to October 2017, soil bacterial species diversity slightly increased whereas species richness decreased in both control and roof plots. Moreover, soil bacterial species richness more decreased in roof plots than in controls. Combining these results, soil bacterial activity might have been altered by simulated drought.

• Proceedings of the KSRS Conference
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• 2009.03a
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• pp.354-359
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• 2009

Land cover types of Hustai National Park (HNP) in Mongolia, a hotspot area with rare species, were classified and their temporal changes were evaluated using Landsat MSS TM/ETM data between 1994 and 2000. Maximum likelihood classification analysis showed an overall accuracy of 88.0% and 85.0% for the 1994 and 2000 images, respectively. Kappa coefficients associated with the classification were resulted to 0.85 for 1994 and 0.82 for 2000 image. Land cover types revealed significant temporal changes in the classification maps between 1994 and 2000. The area has increased considerably by $166.5km^2$ for mountain steppe. By contrast, agricultural areas and degraded areas affected by human being activity were decreased by $46.1km^2$ and $194.8km^2$ over the six year span, respectively. These areas were replaced by mountain steppe area. Specifically, forest area was noticeably fragmented, accompanied by the decrease of $\sim400$ ha. The forest area revealed a pattern with systematic gain and loss associated with the specific phenomenon called as forest free-south slope. We discussed the potential environmental conditions responsible for the systematic pattern and addressed other biological impacts by outbreaks of forest pests and ungulates.

• Journal of Ecology and Environment
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• v.33 no.3
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• pp.223-228
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• 2010

Soil microbes perform crucial roles in the nutrient cycles of forest ecosystems, by effecting the decomposition of organic matter. Enzyme activities have been used to evaluate decomposition rates, as well as microbial activities. The principal objectives of this study were to determine the activities of different soil enzymes, to compare enzyme activities at different elevations, and to elucidate the most important controlling variables for enzyme activities. We conducted a field survey at three sites in Mt. Jumbong on a monthly basis from May, 2004 to September, 2005. Enzyme activities did not change substantially over different seasons. However, the spatial differences were distinct; the lowest elevation site evidenced the lowest levels of enzyme activity. Soils at the lowest elevation were nutrient-depleted soils, and enzyme activities appeared to be affected by precipitation and temperature. However, enzyme activities in fertile soils at high elevations were associated with nutrients and organic matter. The enzyme activities detected in this study differed significantly at the three elevations, and their controlling variables also evidenced different factors.

• Journal of the Korean Society of Earth Science Education
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• v.11 no.3
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• pp.182-192
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• 2018

The purpose of this study was to examine the effects of school forest activities program on elementary students' science process skill and attitude toward science to make suggestions to help develop and extend the program. The subjects of the study were 49 students of two classes. One class of 24 students, experimental class, took developed 10 periods of school forest activities program. While the other class of 25 students, comparative class, took ordinary teacher driven periods using photo materials and study papers. Before and after the program, pre and post test were done. The results of this study can be summarized as follows: First, the school forest activities program didn't have a meaningful effect on students' science process skill. Second, the school forest activities program had a meaningful effect on the improvement of students' attitude toward science. From the interview with experimental class, we could know that students had a favorable impression and high satisfaction level about the activities program.