• Journal of Ecology and Environment
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• v.41 no.5
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• pp.132-141
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• 2017

The importance of forests continues to increase throughout the world, and one of the reasons is that a forest is a major place to emit terpenes, which have been reported to be beneficial to human health. In South Korea, forests occupy about 64% of the total land area and consist mainly of pine and oak trees. Since only a limited number of forests have been analyzed to date, a comprehensive understanding of terpenes emitted from regional forests remains in its infancy in Korea. Here, to gain insights into terpenes from regional forests located in South Korea, we review the characteristics of Korean forests and recent studies on major terpenes emitted from regional forests as well as from native trees dominant in South Korea. We also discuss meteorological factors that affect the terpene emissions in Korean forests. In conclusion, 18 types of terpenes were detected in Korean forests and their compositions in different forests are largely dependent on the dominant plant species in the forest. Moreover, terpene emissions in Korean forests are affected by various environmental factors, including temperature, amount and duration of daylight, season, and age of trees. To improve the understanding of the characteristics of terpene distribution, more studies are required on the terpene production of Korean forests in various regions.

• Journal of the Korean Society of Safety
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• v.26 no.4
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• pp.111-119
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• 2011

This study was designed to provide basic data applicable to fire investigation through consideration of combustion products and propose vulnerability of combustibles through analysis of $CO_2$ emission. In order to achieve these research objectives, characteristics of combustion products such as smoke release rate of each part(raw leaves, branches and barks), $CO_2$ emission and ash production were considered targeting on 6 oak species(Quercus variabilis Blume, Quercus aliena Blume, Quercus serrata, Quercus mongolica Fisch, Quercus dentata Sapling and Quercus acutissima) using cone calorimeter and smoke density tester. As a result, it was found that raw leaves release smoke more relatively than branches and barks, when they burn, and that Quercus variabilis Blume has the highest smoke density. Also, Quercus acutissima released CO and $CO_2$ which are respectively, 6.67 times and 1.43 times more than Quercus variabilis Blume with low $CO_2$ emission. In addition, branches released CO and $CO_2$ more relatively. There was a big difference in ash production among raw leaves(3.1 g), branches(10.5 g) and barks(16.43 g). It was identified that Quercus serrata produces ashes which are nearly 9.95 times more than Quercus variabilis Blume. It demonstrates that Quercus serrata contains relatively higher minerals and that Quercus variabilis Blume can leave lots of traces like stain and carbonization, as it releases smoke a lot and it's difficult to predict visibility, when a forest fire breaks out in its community area. It is also considered that smoke particles containing oil in the air leave strain on the surface of a tree, and that CO and $CO_2$ emission increases, when crown fire to burn branches breaks out.

• Journal of Conservation Science
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• v.37 no.3
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• pp.220-231
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• 2021

The use of digital copies of film-based analog images and the introduction of digital radiographic imaging systems using image plates gradually replace the non-destructive radiationirradiation method of Cultural Heritage. The quality of images obtained from this technique is affected by conditions such as tube voltage, tube current, and exposure time, type of image acquisition medium, distance of the artifacts from the image acquisition medium, and thickness of artifacts. In this study, we evaluated the grayscale image obtained using GE's Computed Radiograhpy (CR) imaging system, the transmission characteristics of the X-ray source for each tree type (pine, chestnut, sawtooth oak, ginkgo) used in wooden Cultural Heritage, and the signal-to-noise ratio (SNR) and contrast. The GE's CR imaging were analyzed using the Duplex wire image quality indicator, line-pair gauges.

• Journal of Periodontal and Implant Science
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• v.54 no.4
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• pp.209-223
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• 2024

Purpose: Periodontal disease is a chronic condition caused by microbial infection and mediated by the host's immune response. Phytotherapy is a therapeutic approach that utilizes a renewable resource capable of supplying less expensive medicines for the world's growing population. This review aimed to present clinical evidence on the use of complementary medicinal herbs in the treatment of periodontal diseases. Methods: Different databases were searched using the terms "herbal" and "periodontitis." All included studies were examined with a focus on herbal indications, type, and prescription length. Dentists' therapeutic and prophylactic herbal prescribing habits were also assessed. Results: Various herbs such as turmeric, neem, aloe-vera, pomegranate, catechu, tulsi, cloves, lemon grass, green tea, tea tree oil, peppermint, garlic, pineapple, oak bark, babul, bakul, sage, coriander, moringa, amla, guava, and grape seed extract have been used in the treatment of periodontitis. These herbs have been reported to exhibit a range of therapeutic effects, including anti-inflammatory, antiplaque, antihalitosis, antiresorptive, antioxidant, antibacterial, antifungal, antiviral, and antimicrobial properties. These components can be utilized in various forms such as mouth rinse, gel, oil, toothpaste, aqueous extract, mouthwash, or tooth powder. Conclusions: Several readily available herbal formulations are now available on the market and have been shown to be effective as supplemental periodontal phytotherapy. However, these should be used under the supervision of a dental professional to ensure optimal benefits and effectiveness. Therefore, it is necessary to improve the understanding of suggested herbal prescription practices among dental professionals.

• Journal of Mushroom
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• v.2 no.4
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• pp.175-183
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• 2004

We carried out survey of a pine mushroom picking district and its vegetation environment for increase and maintainment of its production in Kyonggi province. The district which we could pick up pine mushroom among the nineteen surveyed district were sixteen such as Geoleun ri Gangcheon myeon Yeoju gun Kyonggi do, etc. and total yields were 470~600 kg in Kyonggi province. The temperature of atmosphere and earth in Yeoju and Bonghwa were droped to $19^{\circ}C$ at 5~7th september and maintained from $12^{\circ}C{\sim}18^{\circ}C$ during the a pine mushroom picking period. The density of a pine tree per $100m^2$ was 5.1~27.1 trees, the years of it was 15~50years old and height was 4~11 meter. The pine tree in a pine mushroom picking district was competed with oak trees, azaleas, lacquers, etc. The depth of organic materials accumulated on the pine mushroom mycelium layer was 4.5 cm in Yeoju. The soil texture of a pine mushroom picking district was almost sandy, soil pH was 4.3~5.1 and organic material content was 3.91~8.28%.

• Korean Journal of Microbiology
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• v.37 no.4
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• pp.265-272
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• 2001

The diversity of acid-tolerant epiphytic bacterial communities on deciduous oak tree (Quercus dentate Thunb.) leaves was examined both in the natural forest area with a clean air and in the industrial estate to assess effects of acidic depositions to the phyllosphere using 16S rDNA sequence data. A total of 444 acid-tolerant epiphytic bacterial clones were obtained, resulting in 17 phylotypes by performing a analysis of restriction fragment length polymorphism (RFLP) for PCR-amplified 16S rDNA products. A very low diversity of dominating acid tolerant bacterial communities in both areas was found, just 2 subphyla groups, $\gamma$-Proteobacteria and low-G+C gram-positive bacteria. As tree leaves grow older, diversities of acid-tolerant bacteria on them significantly increased. The community structure of acid-tolerant epiphytic bacteria consisted of Pseudomonas and Enterobacteriaceae groups in the $\gamma$-Proteobacteria subphylum, and Streptococcaceae and Staphylococcus groups in the low-G+C gram-positive bacteria subphylum. The direct influence of acidic depositions on bacterial phylogenetic composition could not be detected especially when higher taxonomic levels such as subphylum, but at narrower or finer levels it could be observed by a detection of Xanthomonadales group belonged to the $\gamma$-Proteobacteria only in the industrial area and of Acetobacteraceae group belonged to the $\alpha$-Proteobacteria. There remains that these specific acid-tolerant epiphytic bacterial groups could be used as indicators for assessing effects of acidic depositions on the phyllosphere.

• Korean Journal of Environment and Ecology
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• v.30 no.2
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• pp.199-213
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• 2016

This study aimed to analyze the vegetation characteristics of the coastal forests and to figure out if there is possibilities to develop the forests into mixed stand multistory forests and to suggest some sound management practices. The vegetat- ion structure and flora of four sites; Kijipo, Chunjangdae, Janghang and Kusipo in the west coastal forests in Korea were investigated and analyzed in the present study. In the every site, Pinus thunbergii was dominating the tree layer in the forests. And P. densiflora, Robinia pseudoacacia, Quercus serrata, Prunus sargentii var. sargentii, Q. acutissima and Castanea crenata were dominating the subtree layers in some sites. P. thunbergii stands in four sites would maintain for a while since the populat- ion density of middle aged group is higher than those of young and old groups. According to the geographical location conditions, there is a possibility that the coastal forests in Kusipo site would progress into oak tree stands in the long run. The biodiversity was quite high to have 205 taxa in the study sites. To induce the coastal forests into multistory forests, P. thunbergii stands need to be thinned. And then creating the environment including making some pathways and site usage rest-riction is needed to let new diverse plants could come in and grow for a success-ful multistory forests.

• Korean Journal of Environment and Ecology
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• v.33 no.5
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• pp.565-577
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• 2019

The purpose of this study was to understand the factors influencing the decline and the patterns of changes in Abies nephrolepis populations on Mt. Seorak. We installed permanent quadrats in the areas of the Gwittagicheongbong (peak), Gwanmoneungseon (ridge), and the Seorak Falls and have monitored the community structure, population dynamics, radial growth, and vitality in the quadrats since 2009. Excluding the Seorak Falls, the three research sites showed a three-layer structure in which the low-tree layer forms the canopy. Major tree species were Khingan fir, Korean arborvitae, Mongolian oak, Erman's birch, and Korean maple. The significance of Khingan fir in Seorak Falls decreased from 45.3% in 2009 to 36.8% in 2018. The number of shoots ($DBH{\geq}5cm$) was highest at 1,800 individuals/ha and 1,700 individuals/ha at the Gwittagicheongbong 2 and the Gwanmoneungseon, respectively. The mortality rates over the past 10 years were very high, at 38.3% and 35.3%, respectively, in the Gwittagicheongbong 1 and Seorak Falls. The most stable inverse J-shaped distribution in the Gwittagicheongbong 1 area was shown in the size-frequency distribution of the Khingan fir populations. The average annual ring growth of the Khingan fir was 0.96 ~ 1.73 mm/year, and the ring growth tended to decrease in the areas of Gwittagicheongbong 1, Gwanmoneungseon, and Seorak Falls, where the vitality was low. If the monitoring process continues, it will be possible to obtain basic data for the conservation and management of subalpine vegetation.

• Korean Journal of Environment and Ecology
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• v.32 no.6
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• pp.646-657
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• 2018

The purpose of this study was to understand the ecological characteristics and vegetation structure of Mt. Daedun Provincial Park by setting up and surveying 42 plots ($100m^2$). The analysis using the TWINSPAN and DCA techniques found seven community groups: Quercus aliena community, Larix kaempferi community, Pinus densiflora community, Quercus variabilis-Quercus serrata community, Pinus rigida community, Carpinus tschonoskii community, and Quercus mongolica community. The results of a vegetation structure analysis showed that the dominant species of each community were likely to maintain the present structure, but, in the case of Pinus densiflora community, it is necessary to monitor the forest succession because of the competition with oak trees. The results of the DBH (diameter of breast height) analysis showed that the species in DBH 20-24cm and over 26cm were many observed, indicating that the communities were becoming stable. It is likely that the dominant species of tree canopies will maintain their state unless the unexpected physical environment changes, serious disturbance, pests or diseases occur. The results of the tree rings and annual growth analysis showed that the dominant trees had an average age of more than 40 years. The average annual growth was the highest for Quercus variabilis in community I at $3.51{\pm}2.39mm$ and the lowest for Quercus mongolica in community VII at $1.61{\pm}0.90mm$.

• Korean Journal of Environmental Biology
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• v.35 no.3
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• pp.413-425
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• 2017

This manuscript describes the relationship between climate change and forest growth, forest species, carbon stocks, and tree mortality. 1) In the aspect of forest growth, the growth of major coniferous species, including Pinus densiflora, had a negative correlation with temperature. On the other hand, major deciduous oak species, including Quercus variabilis and Quercus mongolica, had a positive correlation with temperature. 2) When considered in the aspect of the forest species distribution, various models commonly showed a decrease in the distribution of coniferous species and an increase in oak species due to climate change in the medium to long term. 3) From the carbon stock perspective, there was a difference in the estimation according to the status of forest management. Most of Korean forests will mature to become over-matured forest after year 2030 and are estimated to produce approximately 410 million ton forest biomass until 2090 with the current cutting regulations for sustainable forest management announced by the Korean Forest Service. 4) In the forest mortality, the mortality rate of the major coniferous species showed a clear tendency to increase higher temperatures while it decreased for the oak species with no verification of statistical significance. Moreover, the mortality of the subalpine coniferous species was projected to progress rapidly. considering the overall impacts described above, there should be a management strategy for coniferous species that are relatively vulnerable to climate change. Moreover, a sustainable forest plan in the aspect of ecosystem services, carbon sequestration and storage, which is linked to global issues such as Sustainable Development Goals, ecosystem services and negative emission.