• The Journal of the Petrological Society of Korea
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• v.26 no.3
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• pp.221-234
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• 2017

The Baengnokdam, the summit crater of Mt. Halla, is one of the representative geosites of World Natural Heritage and Global Geopark in Jeju Island. The crater is marked by two distinctive volcanic lithofacies that comprise: 1) a trachytic lava dome to the west of the crater and 2) trachybasaltic lava flow units covering the gentle eastern slope of the mountain. This study focuses on understanding the formative process of this peculiar volcanic lithofacies association at the summit of Mt. Halla through field observation and optically stimulated luminescence (OSL) dating of the sediments underlying the craterforming volcanics. The trachyte dome to the west of the crater is subdivided into 3 facies units that include: 1) the trachyte breccias originating from initial dome collapse, 2) the trachyte lava-flow unit and 3) the domal main body. On the other side, the trachybasalt is subdivided into 2 facies units that include: 1) the spatter and scoria deposit from the early explosive eruption and 2) lava-flow unit from the later effusion eruption. Quartz OSL dating on the sediments underlying the trachyte breccias and the trachybasaltic lava-flow unit reveals ages of ca. 37 ka and ca. 21 ka, respectively. The results point toward that the Baengnokdam summit crater was formed by eruption of trachybasaltic magma at about 19~21 ka after the trachyte dome formed later than 37 ka.

• Korean Journal of Environment and Ecology
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• v.25 no.4
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• pp.562-572
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• 2011

This study is to examine the environmental characteristics of subpopulations of Ilex crenata var. microphyllla Max. distributed in the east-west slopes of Mt. Halla National Park based on analyzing the factors of environment, vegetation and soil. The result of the TWINSAPN analysis conducted on 56 study plots between the altitudes of 500 m and 1600 m of east-west slopes of Mt. Halla National Park can be divided into five communities-Prunus maximowiczii Rupr., Manshurian fullmoon Maple, Carpinus tschonoskii Max., Daphniphyllum macropodum Miq., Quercus serrata Thunb. ex Murray and Pinus thunbergil Parl. Among these communities, the plot with high importance percentage of the subpopulation of Ilex crenata var. microphyllla Max., is the Carpinus tschonoskii Max.-Daphniphyllum macropodum Miq. included in the altitude of 600m~1200m radius. The dominant species of the upper shrub layer was Carpinus tschonoskii Max.(I.P.: 29.82%) while the dominant species of the canopy layer was Daphniphyllum macropodum Miq.(I.P.: 26.76%). For the understory layer the dominant species was Ilex crenata var. microphyllla Max.. Species diversity index was on the low end with 0.7424, indicating the stably formed climax community of Carpinus tschonoskii Max.. The analysis of soil properties showed high concentrations of organic matters, available phosphate and Ca, Mg, the high importance percentage of the of Ilex crenata var. microphyllla Max. is found in altitude of 600m~800m on the eastern slope and the altitude of 800m~1,000m radius on the west slope. This region is included in the southern part of the cold/hot forest zone, its high importance percentage of Carpinus tschonoskii Max. and low in the species diversity index of 0.7424, and has formed stable climax community of Carpinus tschonoskii Max. in Mt. Halla.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.3
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• pp.1-14
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• 2019

With a view to developing a database of death years of Korean firs (Abies koreana) at Yeongsil in Mt. Halla and investigating their abrupt inter-annual growth reduction tree-ring analysis was employed. To this end, 10 living trees (YSL) were selected to establish a master chronology and 20 dead trees were used to date their dead years. To investigate the difference in death years by death types, 10 trees, which remained standing (YSSD) out of the 20 dead trees were selected. The rest 10 dead trees were already fallen (YSFD). Two increment cores per tree at breast height were extracted in contour direction using an increment borer. A 106-year master chronology (1911-2016) was successfully established from the 10 YSLs. Through cross-dating between individual YSSD time series and the master chronology, it was verified that 1 YSSD was dead in summer 1978, 1 YSSD between autumn 1999 and spring 2000, 2 YSSDs in summer 2007, 1 YSSD in summer 2010, 1 YSSD in summer 2012, and 1 YSSD in summer 2013. The youngest tree rings of 2 YSSDs having no bark were in 1977 and 2002. For the YSFDs, it was verified that 1 YSFD was dead between autumn 1997 and spring 1998, 1 YSFD between autumn 2001 and spring 2002, 2 YSFDs between autumn 2009 and spring 2010, 1 YSFD in summer 2010, and 2 YSFDs between autumn 2012 and spring 2013, while the youngest tree rings of 2 YSFDs having no bark were in 1989 and 2004. To note, the death years of two trees, one from each death type (YSSD and YSFD), could not be verified due to poor cross-dating with the master chronology. The inter-annual growth reductions of YSSD and YSFD occurred more frequently and intensively than YSL. Typically, the YSFD showed the most frequent and intensive inter-annual growth reduction. On comparing the inter-annual growth reductions with the corresponding records of typhoons however we could not find any reliable relationship. Finally, from prior reports and results of the current study it can be concluded that the death and abrupt growth reduction of korean fir at Yeongsil in Mt. Halla are not caused by only a certain environmental factor but various factors.

• The Korean Journal of Ecology
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• v.10 no.3
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• pp.109-118
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• 1987

The production and decomposition rates of litters were studied in three mountains, Mt. Halla, Mt. So-back and Mt. Tae-back. The amounts of N, P, K, Ca and Na in the soils were measured and the relationships between the mineral nutrients and decay rates were reserched, The annual litter production was the most as $1, 077.3g/m^2$ and the least as $248.0g/m^2$ in a stand of Quercus acutissima at 820m of the Mt. So-back and at 1, 350m of the Mt. So-back among the study sites, respectively. The decay rates of litter was the highest as k=0.448 and the lowest as k=0.082 in a stand of Q. acutissima at 820m of the Mt. So-back and at 1, 450m of the Mt. Tae-back at 1, 450m of the Mt. Tae-back among the study sites. The higher altitude was, the slower the decay rates were. The annual contents of mineral nutrient and their amounts inputted into the forest soil were proportional to the decay rate of organic metters.

• Korean Journal of Plant Resources
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• v.20 no.1
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• pp.89-92
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• 2007

The purpose of this study was to establish basic database on Sorbus alnifolia by investigating, analyzing and comparing characteristics of leaf, and then foster good cultivar on each morphological characteristics - leaf length, leaf width, petiole length, left lateral vein, right lateral vein. Leaf length and leaf width in Osan showed distinct tendency in comparison with the whole mean : 103.4mm and 63.3mm, 86.4mm and 62.9mm, respectively. Populations of Mt. Dukyoo and Mt. Halla showed leaf length of 52.8mm and 58.2mm respectively 32.6% and 39% lower than the mean of ten population. Leaf width of Mt. Gwangyang and Mt. Chink was 52.8mm and 51.9mm, respectively 17.6% and 16.2% lower than whole mean, respectively, and showed the lowest tendency among ten selected populations.

• Journal of Korean Society of Forest Science
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• v.105 no.1
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• pp.63-72
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• 2016

A study was conducted to evaluate the effect of collected region(Bongpyeong in Gangwon, 690 m, Mt. Halla in Jeju, 1,085 m), pre-treatment (stratification, soaked in distilled water or $GA_3$) and shading (control, 50%, 80%) on seed emergence and seedlings growth of Ligularia fischeri. The result showed that seed emergence (%) of L. fischeri were 6.9~75.5% (Gangwon : 6.9~32.8%, Halla : 22.2~75.5%). Maximum seed emergence (%) of 32.8 (Gangwon) and 75.5 (Halla) were achieved for seeds were stratified, soaked in distilled water, and under non-shading for L. fischeri (Gangwon), whereas seeds were stratified, soaked in $GA_3$ 100 ppm, and under 80% shading for L. fischeri (Halla). In this study, the best seedling vigor index (SVI) of L. fischeri (Gangwon) and L. fischeri (Halla) were obtained when seeds were stratified, soaked in distilled water, and under 50% shading. The survival rate of potted seedlings for L. fischeri (Halla) were 100% of all shading conditions, but there were decreased by 77.8%, 61.1%, 55.6%, as an increasing shading rate (con, 50%, 80%) for L. fischeri (Gangwon). Therefore, good seedlings were obtained when seed (Mt. Halla) of L. fischeri were stratified, soaked in distilled water, and under 50% shading, and then seedlings were transferred in pot.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2005.11a
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• pp.394-396
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• 2005

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2010.04a
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• pp.139-141
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• 2010

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.11a
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• pp.355-356
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• 2004

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.04a
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• pp.295-297
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• 1999