• Journal of Forest and Environmental Science
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• 제38권3호
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• pp.159-173
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• 2022

Genus of Rhododendron has been used in traditional medicine since ancient times and is known to be effective in immune function, inflammation, and cold symptoms. And the reason for this activity is the flavanonol type among flavonoids in the genus of Rhododendron. Among the flavanonol types, Taxifolin-3-O-arabinopyranoside was isolated from the root of native R. mucronulatum in Korea, and the structure was finally identified through HPLC, LC-MS/MS, ¹H-NMR, and ¹³C-NMR. Taxifolin-3-O-arabinopyranoside is a compound mainly found in R. mucronulatum, a representative species of the genus of Rhododendron, and exhibits antioxidant, anti-inflammatory, and anti-atopic activities. In this study, Taxifolin-3-O-arabinopyranoside was chemotaxonomic significant in 5 species of the genus Rhododendron native to Korea (R. mucronulatum, R. mucronulatum var. ciliatum, R. schlippenbachii, R. yedoense var. Poukhanense, R. japonicum for. Flavum). Compared with the existing literature, Taxifolin-3-O-arabinopyranoside was identified for the first time in 4 species of Rhododendron except for the R. mucronulatum.

• 농업생명과학연구
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• 제52권6호
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• pp.37-47
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• 2018

본 연구의 목적은 전국에 분포하는 일본잎갈나무 임분에 대해 산림시업 수행이 직경분포변화에 미치는 영향에 대해 분석하였다. 본 연구에 사용한 자료는 국가산림자원조사 중 시업지 232plots, 비시업지 47plots의 고정표본점 자료를 활용하였다. 직경분포모델은 Weibull 누적분포함수를 사용하였으며, 분석 방법에는 백분위(Percentile)에 근거한 직경모형추정, 백분위(Percentile)에 대한 모수복구 방법을 사용하였다. 개발한 모델을 이용하여 산림시업의 수행여부에 따른 시나리오(임령, 지위지수, 임분밀도) 별임분생장량을 예측한 결과, 시업지 임분의 최대임목본수를 차지하는 평균 흉고직경의 이동이 비시업지 임분에 비해 이동량과 생장량이 더 높게 나타났으며, 대경목이 차지하는 비율 또한 시업지 임분이 높게 예측되었다. 본 연구의 결과는 직경급에 따른 목재생산량의 장기적인 예측과 동적인 임분구조 해석에 기초적인 정보를 제공할 수 있을 것으로 사료되어진다.

• Journal of Forest and Environmental Science
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• 제38권4호
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• pp.219-228
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• 2022

This study examined the relationship between the number of forest fires and days with no rainfall based on the national forest fire statistics data of the Korea Forest Service and meteorological data from the Open MET Data Portal of the Korea Meteorological Administration (KMA; data.kma.go.kr) for the last 30 years (1991-2021). As for the trend in precipitation amount and non-rainfall days, the rainfall and the days with rainfall decreased in 2010 compared to those in 1990s. In terms of the number of forest fires that occurred in February-May accounted for 75% of the total number of forest fires, followed by 29% in April and 25% in March. In 2000s, the total number of forest fires was 5,226, indicating the highest forest fire activity. To analyze the relationship between regional distribution of non-rainfall periods (days) and number of forest fires, the non-rainfall period was categorized into five groups (0 days, 1-10 days, 11-20 days, 21-30 days, and 31 days or longer). During the spring fire danger season, the number of forest fires was the largest when the non-rainfall period was 11-20 days; during the autumn fire precaution period, the number of forest fires was the largest when the non-rainfall period was 1-10 days, 11-20 days, and 21-30 days, showing differences in the duration of forest fire occurrence by region. The 30-year trend indicated that large forest fires occurred only between February and May, and in terms of the relationship with the non-rainfall period groups, large fires occurred when the non-rainfall period was 1-10 days. This signifies that in spring season, the dry period continued throughout the country, indicating that even a short duration of consecutive non-rainfall days poses a high risk of large forest fires.

• Journal of Microbiology
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• 제45권6호
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• pp.485-491
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• 2007

The effects of biological pretreatment on the Japanese red pine Pinus densiflora, was evaluated after exposure to three white rot fungi Ceriporia lacerata, Stereum hirsutum, and Polyporus brumalis. Change in chemical composition, structural modification, and their susceptibility to enzymatic saccharification in the degraded wood were analyzed. Of the three white rot fungi tested, S. hirsutum selectively degraded the lignin of this sortwood rather than the holocellulose component. After eight weeks of pretreatment with S. hirsutum, total weight loss was 10.7%, while lignin loss was the highest at 14.52% among the tested samples. However, holocellulose loss was lower at 7.81 % compared to those of C. lacerata and P. brumalis. Extracelluar enzymes from S. hirsutum showed higher activity of ligninase and lower activity of cellulase than those from other white rot fungi. Thus, total weight loss and changes in chemical composition of the Japanese red pine was well correlated with the enzyme activities related with lignin- and cellulose degradation in these fungi. Based on the data obtained from analysis of physical characterization of degraded wood by X-ray Diffractometry (XRD) and pore size distribution, S. hirsutum was considered as an effective potential fungus for biological pretreatment. In particular, the increase of available pore size of over 120 nm in pretreated wood powder with S. hirsutum made enzymes accessible for further enzymatic saccharification. When Japanese red pine chips treated with S. hirsutum were enzymatically saccharified using commercial enzymes (Cellulclast 1.5 L and Novozyme 188), sugar yield was greatly increased (21.01 %) compared to non-pre treated control samples, indicating that white rot fungus S. hirsutum provides an effective process in increasing sugar yield from woody biomass.

• 원예과학기술지
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• 제34권3호
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• pp.383-395
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• 2016

This study investigated the effect of exogenous hydrogen peroxide ($H_2O_2$) on the antioxidant responses and growth of warm-season turfgrass (Zoysia japonica Steud.) and cool-season turfgrass (Poa pratensis L.) subjected to drought stress. Compared with control plants that were not pretreated with $H_2O_2$, plants pretreated with $H_2O_2$ had significantly greater fresh and dry weights of shoots and roots, and increased water content. $H_2O_2$ pretreatments before drought stress significantly decreased the concentrations of malondialdehyde and $H_2O_2$. DPPH radical scavenging and glutathione activities were significantly increased. The responsive activities of the antioxidant enzymes superoxide dismutase, ascorbate peroxidase, catalase, and peroxidase were also significantly enhanced. Our results suggest that exogenous $H_2O_2$ could improve the growth of warm-season and cool-season turfgrass under drought stress by increasing the activity of their antioxidant enzymes, while decreasing lipid peroxidation.

• Journal of the Korean Wood Science and Technology
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• 제31권1호
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• pp.32-40
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• 2003

항산화활성이 우수한 주목 심재 에탄올 추출물로부터 Sephadex LH-20, centrifugal partition chromatography (CPC), silica gel column chromatography 등을 이용하여 5종의 화합물을 단리하였으며, NMR, Mass spectrometry 등의 기기분석 결과 taxane 화합물인 taxusin를 비롯하여 lignan인 isolariciresinol (4, 4', 9, 9'-tetrahydroxy-3', 5-dimethoxy-2, 7'-cyclolignan), lariciresinol (4, 4', 9-trihydroxy-3, 3'-dimethoxy-7, 9'-epoxylignan), taxiresinol (3, 4, 4', 9-tetrahydroxy-3'-methoxy-7, 9'-epoxylignan) 및 isotaxiresinol (3', 4, 4', 9, 9'-pentahydroxy-5-methoxy-2, 7'-cyclolignan)을 각각 동정하였다. 이들 단리된 화합물의 프리라디칼 소거능을 측정하여 항산화활성을 검정한 결과 taxusin을 제외한 3종의 lignan 화합물인 isolariciresinol, lariciresinol, isotaxiresinol 모두 천연항산화제 및 합성항산화제보다 높은 라디칼 소거능을 나타내어 항산화활성이 우수한 것으로 판명되었다. 이상의 결과 주목의 심재 에탄올 조추출물의 높은 항산화활성은 이들 성분에 기인하는 것으로 사료되었다.

• 한국농림기상학회지
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• 제7권2호
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• pp.156-163
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• 2005

버즘나무와 백합나무의 오존에 대한 생리 생화학적인 반응 특성을 비교하고, 단기간 동안의 노출에 따른 피해 및 내성 반응을 알아보고자 본 연구를 수행하였다. 두 수종 1년생 묘목을 100 ppb의 오존에 2, 4, 8 시간/일 동안 노출시키며 1주일간 광합성, 기공전도도, 오존흡입량을 측정하고 1주일 후 광화학 효율 및 탄소고정 효율, 엽록소 함량 및 항산화효소인 SOD의 활성을 측정하였다. 광합성과 기공전도도는 버즘나무의 경우 2시간 처리구는 감소하지 않았지만 오존 처리 시간이 길어질수록 감소하였으며, 백합나무는 버즘나무보다 민감하게 반응하여 2시간 처리구에서도 광합성과 기공전도도의 감소가 나타났으며, 오존 처리 시간이 길어질수록 더욱 많이 감소되었다 엽록소 형광반응을 이용한 광화학을 측정에서는 두 수종 모두에서 오존 처리 시간에 빠른 광화학효율의 차이가 크게 나타나지 않았지만, 탄소고정효율에 있어서는 오존 처리 시간이 길어질수록 매우 많이 감소하였으며, 백합나무의 감소 폭이 더 켰다. 엽록소 함량은 두 수종 모두 큰 변화가 나타나지 않았지만 SOD 활성에서는 수종간에 큰 차이가 나타났는데 버즘나무 2시간 처리구에서는 증가하였으며, 처리 시간이 증가함에 따라 감소하였지만 백합나무에 비하여 감소 폭이 적었다. 따라서 오존에 대해서 버즘나무보다 백합나무가 민감하게 반응하며 내성이 낮은 것으로 판단되었다.

• The Korean Journal of Ecology
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• 제23권2호
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• pp.169-173
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• 2000

Seasonal distribution of ectomycorrhizal associations in various types of forest in a boreal forest in Manitoba. Canada was investigated. Alsohe relationship between ectomycorrhizal growth and pine pollen nutrients was examined. In four different forest stands, ectomycorrhizas tended to be lower in the spring than in the summer and fall samples. In addition. a mature jack pine (Pinus banksiana) stand showed higher mycorrhizal activities than a young jack pine stand. Growth of Suillus brevipes hyphae wa ts stimulated by additions of pollen representing mean pollen deposition in Mistik Creek study area after 30 and 70 days of growth with dextrose availability. This result suggests that the peak ectomycorrhizal activity is followed by pollen deposition in the study region and therefore, addition of pine and spruce pollen in early or middle of June in the boreal forest can be an important seasonal nutrient source for ectomycorrhizal growth.

• 한국환경교육학회지:환경교육
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• 제18권2호
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• pp.90-100
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• 2005

This study was intended to investigate effects of building school forests on elementary school students, including changes in mental image of school, attitude toward nature and forest, and awareness of their relationship with school forest. The total number of 770 drawings and 1,124 writings were collected to be analyzed from three elementary schools. The results showed that there were significant differences between two student groups, respectively forest school group versus non-forest school group, in their mental image of school. For instance, more often observed in the drawings of forest school group students than their counterparts were natural and human elements, activities associated with nature, and natural or human elements located at central area. Also, more frequently found in the writings of forest school group students than their counterparts were letter-style sentences, stories about school forests, inherent values on nature and forest, and curiosity regarding the nature. These results seem to indicate that in order to materialize educational value of school forests, practical workshops for teachers need to be held as soon as possible and new activity models for students should be developed. In addition to that, long-term research on effectiveness of school forest have to be conducted to a number of schools.

• 한국농림기상학회지
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• 제16권4호
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• pp.336-342
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• 2014

본 연구는 우리나라의 광역지자체의 산림지 온실가스 배출량을 시범산정하기 위해 수행되었다. 온실가스 배출량은 국가 온실가스 인벤토리 산정 지침에 따라 산정하였으며, 이를 위해 임업통계연보 및 산림관련 활동 자료 및 배출계수를 이용하였다. 그 결과 산림지의 2011년 총 배출량은 -58,711Gg $CO_2eq.$, 벌채, 연료재 수집, 산불에 의한 배출량은 19,896Gg $CO_2eq.$로 나타났다. 2011년을 기준으로 산림지에서는 온실가스를 흡수하는 것으로 나타났고, 순 배출량은 -38,815Gg $CO_2eq.$로 나타났다. 광역지자체 별로는 강원도에서 온실가스를 가장 많이 흡수하는 것으로 나타났다. 본 연구의 산정결과는 현재 중복산정을 최대한 배제하고자 많은 통계를 활용하지 않은 것으로, 향후 활동자료 및 배출계수 등을 보완하여 산정할 필요가 있을 것으로 사료된다.