• 한국환경생물학회:학술대회논문집
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• 한국환경생물학회 2004년도 학술대회
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• pp.44-44
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• 2004

• 한국작물학회:학술대회논문집
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• 한국작물학회 2020년도 춘계학술대회
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• pp.173-173
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• 2020

• 한국작물학회:학술대회논문집
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• 한국작물학회 2020년도 춘계학술대회
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• pp.151-151
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• 2020

• 한국산림과학회지
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• 제99권5호
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• pp.682-685
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• 2010

Coring has been widely used to measure annual increment in temperate forest ecosystems. This method is attractive because cores can be taken in just one visit. However, the accuracy of this method has not been tested. We expected coring to be less accurate than band dendrometers because of the eccentricity of tree growth. We studied 41 trees at the Long Term Experimental Forest in Mt. Gyebang, which has been monitored with band dendrometers since 1996. We collected two tree cores from the south and north face of each tree, 10 cm below the growth band. Increment cores were measured to 0.01 mm under stereomicroscopy. Annual growth from 1997 to 2006 was 3.2 mm $yr^{-1}$ for Quercus mongolica, 3.5 mm $yr^{-1}$ for Kalopanax septemlobus, and 5.7 mm $yr^{-1}$ for Pinus densiflora. The difference between the two methods was 10% for Q. mongolica, 14% for K. septemlobus, and 4% for P. densiflora. Compaction in the corer and shrinkage during drying decreased diameter increment by 5.6% and 1.0% on P. densiflora, respectively. This study suggests that the two methods for annual increment measurement are very similar, but species specificity should be concerned for direct comparison.

• Journal of Forest and Environmental Science
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• 제35권4호
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• pp.213-222
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• 2019

Climate change has been intensifying and affecting forest ecosystems. Over the years, the intensity and frequency of climate change have increased and the effects of climate change have been aggravating due to cumulative greenhouse gases such as CO₂, which has resulted in several negative consequences, drought being the main threat among all. Drought affects forest ecosystems directly and indirectly. Insufficient soil moisture, due to drought, may affect the growth of plants and soil respiration (SR), and soil temperature may increase because of desiccated soil. In addition, the mortality rate of plants and soil microorganisms increases. As a result, these effects could reduce forest productivity. Thus, in this article, we have presented various research studies on artificial drought using throughfall exclusion, and we have mainly focused on SR, which is significantly related to forest productivity. The research studies done worldwide were sorted as per the main groups of Köppen-Geiger climate classification and intensively reviewed, especially in tropical climates and temperate climates. We briefly reviewed the properties among the exclusion experiments about the temperate climate, which mostly includes Korean forests. Our review is not a proof of concept, but an assumption for adequate investigation of drought effects in the Korean forest.

• 식물분류학회지
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• 제34권1호
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• pp.1-7
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• 2004

국내 미기록종인 수국과 (Hydrangeaceae)의 성널수국 (Hydrangea luteovenosa Koidz.)을 제주도 한라산의 성널오름 지역에서 채집하였다. 본 분류군은 습성, 잎의 길이와 폭, 엽병의 길이, 양성화의 꽃잎과 거치의 형태, 자방의 위치, 측맥과 수술의 수의 특정에 의해 한국산 산수국 [Hydrangea serrata (Thunb.) Ser.]과 등수국 [H. petiolaris Siebold & Zucc.]과 뚜렷하게 구별되었다.

• The Korean Journal of Ecology
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• 제17권3호
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• pp.391-413
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• 1994

The northernmost type of the monogolian oak forests in the Russian Far East was studied in terma of syntaxonomy and synchorology. Hand-sorting method, computer program TWIN-SPAN, CANOCO and SYN-TAX III were engaged for the classification and data analysis. Correlation between plant communitie and environmental factors was analyzed by DCA (Detrended Correspondence Analysis) using NeCD (Net Contribution Degree) of species. Three plant communities were recognized: the Abieti holophyllae-Quercetum mongolicae, the Lespedezo-quercetum mongolicas and the Rosa ussuriensis-Quercus mongolica communit. They were included into the alliance Jeffersonio-Quercion monogolicae which is representative to the cool-Temperate forests mixed by conierous and broadleaved trees in southern Sikhote Alin. Human impact was signified as the most important factor to interpret the disjunction of plant communities of which DCA ordination yielded sharp contrasting objects (i.e. stands and species). In the amhi-Tonghae region, alaogous vegetation types such as the Jeffersonio-Quercion monogolicae of Russian Far East, the Quercion grosseserratae of Japanese Hokkaido and the Pino koraiensis-Quercion monogolicae of Koream peninusula were reviewed in terms of similarity of species composition and stratum structure. It is signified that the Jeffersonio-Quercion monogolicae was one of the continental types more similar to Korean alliance that to Japanese one.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.376-377
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• 2009

In the study the affect of $SiO_$ depending on the characteristics of break-down, we have experimented the break-down for the $SiO_$ and variable temperature change after mading nano $SiO_$ of the diameter 12 [nm] at the epoxy resin. As the experimental results, we have continued that the break-down strength is increased at the adding change but the break-down strength is decreased again as the 0.4 [wt%] standard. Also, the break-down voltage is not changed at 25, 50 [$^{\circ}C$] as the temperate change. But break-down voltage is largely changed when temperate is rising up.

• 한국초지조사료학회지
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• 제13권2호
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• pp.112-121
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• 1993

To study management practices suitable for the least production loss of temperate pasture under summer stress, two different cutting dates (late June and mid July) under summer stress and five different nitrogen treatment application levels (0, 100. 200, 300 and 400 kg/ha) were tried during the trial period between Oct. of 1986 and Oct. of 1989. The late June cutting showed a statistically significant increase of dry matter yield of pasture in comparison with the mid-July cutting(P<0.05). Nitrogen application also gave significant increase in dry matter yield. Botanical composition at the 4th cuttings in 1988 and 1989 was dominated by weeds to the level of 50%, Application ofnitrogen at 200 kgs per ha was found to be the best with production of grasses at 70%, legumes at 10 % and weeds at 20% in botanical composition comparison of pastures at the 4th cutting time the last year, showing a great decrease of weeds. K contents of pasture in June cuttings showed to be more than them in July cutting, and N and Na contents increased with increases of the nitrogen application level. It was concluded that treatment with June cutting and nitrogen application of 200 kg per ha was a way to keep temperate pasture from summer stress in the Cheju area.

• Journal of Ecology and Environment
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• 제31권3호
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• pp.193-200
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• 2008

We obtained quantitative information on leaf unfolding and leaf shedding by observing 45 species of cool temperate deciduous trees in an arboretum over 5 growing seasons. These trees were in leaf (the foliage period) for 207 days on average after 1 April; 50% of leaves had been shed by 192 days after 1 April. Duration from the start of leaf unfolding to 50% leaf shedding was 157 days on average. Leaf unfolding began 35 days on average after 1 April. For leaf unfolding to begin, a$ 51^{\circ}C{\cdot}day$ of cumulated daily mean air temperature above $5^{\circ}C$ from 1 January (modified Kira's warmth index) was needed. Fifty-nine days elapsed between initiation and the final stage of leaf unfolding. The period of net photosynthetic assimilation was 157 days. The species with succeeding- type leaf unfolding associated with the anemochore seed type dominated the early stage of succession, while the species with flush-type leaf unfolding tended to dominate the late stage of succession. Few species were found in regions where late frosts occur after the day when the cumulative temperature for leaf unfolding is achieved. Biological characteristics include time of leaf unfolding, which affects the life history of each species, so that each species occupies its own niche in the stand. We conclude that that leaf phenology, such as timing of leaf unfolding and leaf shedding, is one of the components of each species' ecological characteristics.