• Journal of People, Plants, and Environment
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• v.22 no.6
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• pp.575-582
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• 2019

Moss is used as an important material in indoor landscaping as well as outdoor landscaping. Moss is vivid green during growth and excellent in ornamental value. But when temperature drops, moss stops growth, turns brown or loses its ornamental value. In the present experiment, for the purpose of classifying native mosses according to the growth response to low temperature, the temperature of the plant growth chamber was set to 15℃/5℃ (16h/8h, day/night) and 5℃ (24h) for 8 weeks using nine native moss species. Thereafter, the temperature of the plant growth chamber was set to 20℃, and then the changes of moss block area and moss color were measured. The changes of moss block area and moss color were measured using a Photoshop program, after each moss block was photographed. As a result, Atrichum undulatum (Hedw.). Beauv., Etodon luridus (Griff.) A. Jaeger, Bachythecium plumosum (Hedw.) Schimp, Plagiomnium cuspidatum (Hedw.) T.J. Kop, and Hypnum plumaeforme Wilson showed a small decrease in moss block area at low temperature, and their recovery were the fastest at 20℃. These three species had higher green values at low temperature compared to other species, and the greenness increased rapidly at 20℃. On the other hand, Atrichum undulatum (Hedw.). Beauv., Marchantia polymorpha L., and Thuidium cymbifolium (Mitt.) A. Jaeger showed the smallest block area at low temperature and the lowest recovery even at 20℃. Their green values also decreased significantly at low temperature, and maintained low green value even at 20℃. These results showed that these three moss species are sensitive to low temperature. The remaining Myuroclada maximowiczii, Plagiomnium cuspidatum, and H. erectiusculum showed moderate responses to low temperature compared to other six species of mosses.

• Korean Journal of Environment and Ecology
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• v.31 no.6
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• pp.549-556
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• 2017

The purpose of this study was to investigate the change of spatial distribution of Korean fir (Abies koreana E. H. Wilson) in Mt. Hallasan for the past 10 years. We examined the distribution and crown density between 2006 and 2015 and analyzed the elevation, direction, and regional characteristics. The total area of Korean fir was 626.0ha in 2015, which declined by 112.3ha accounting for 15.2% for the past 10 years compared to 738.3ha in 2006. For the past 10 years, the area of moderately dense Korean fir with the crown density of 41% to 70% decreased by 72.6ha while the area of dense Korean fir with the crown density of 71% or more deceased by 21.3ha. The area with an elevation between 1,510m and 1,600m showed the largest change, accounting for 32.6% of the total declining area. Regarding the distribution by the direction, the area in the southeastern direction decreased by 23.4ha while the area in the southeast and northeast centered on the eastern direction decreased by 62.3ha, which accounted for 55.5% of the total area. Regarding the change of the distribution of Korean fir forest area by the region, the decrease of the area from the Jindallaebat to the top of the mountain was the largest at 84.6ha, or 71.8% of the total decreased area. The Yeongshil Trail area decreased by 25.3ha or 21.5% of the total while the Keundurewat area decreased by 8.0ha or 6.8%. On the contrary, the Bangaeoreum area increased by 5.6ha. The results indicate the large decrease of area of Korean fir forest centered on a particular location of Mt. Hallasan. Considering the changes according to the elevation, direction, and regional characteristics, it can be attributed to increasing frequency of abnormal climates such as typhoons and droughts.

• Journal of Korea Foresty Energy
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• v.20 no.2
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• pp.58-68
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• 2001

This study was carried out to investigate the growth and biomass production of Abies koreana seedlings under different relative light intensity. The 5-year-old potted seedlings were grown for 24 months under different light intensity of 100%, 50%, 30%, 10% and 2% of the natural full light intensity. The results were as follows: 1. Height growth was similar in the seedlings under different light intensities except in 2% of the full sun light intensity, having shown the lowest height growth. 2. Root collar diameter growth was reduced gradually by decreasing of the relative light intensity. 3. The seedlings which were grown under relatively low light intensity showed the later starting date of the stem growth in the next spring and showed the smaller number of new needles, and the smarter number and the shorter length of new shoot of the seedlings. 4. Total dry mass including the dry mass of leaves, shoot and root was reduced by decreasing of the relative light intensity. 5. In case of the seedling grown in one year shading condition, the ratio of the dry mass of current-year needles and stem to that of the above one-year-old needles and stem was ranged from 0.99$\pm$0.25 to 1.06$\pm$0.06 and was not significally different among the seedlings grown under 100%, 50% and 30% of the relative light intensity. And the radio was ranged from 0.60$\pm$0.04 to 0.52$\pm$0.03 in the seedlings grown under 10% and 2% of the relative light intensity, respectively. In case of the seedling grown in two years shading, the ratio of the dry mass of current-year needles and stem to that of the above one-year-old needles and stem was ranged from 0.79$\pm$0.04 to 1.00$\pm$0.03 and was not significally different among the seedlings grown under 100, 50, 30% and 10% of the relative light intensity. And the ratio was 0.29$\pm$0.03 in the seedlings grown under 2% of the relative light intensity, respectively. 6. T/R ratio of the seedlings grown in one year shading condition was ranged from 3.35$\pm$0.33 to 4.61$\pm$0.25 and was not significantly different among the relative light intensities of 100%, 50%, 30% and 10%. The seedlings grown under 2% of relative light intensity showed the highest T/R ratio of 7.36$\pm$0.15. In case of the two years shadings the T/R ratio was ranged from 1.76$\pm$0.11 to 3.12$\pm$0.19 and increased as relative light intensity decreased except 2.01$\pm$0.14 in 2% of relative light intensity.

• Journal of Korean Society of Forest Science
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• v.95 no.1
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• pp.102-112
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• 2006

The change of species composition and stand structure along altitudinal gradients in different aged stands was studied in five natural stands located each at 400 m, 800 m, 1,000 m, and two at 1,300 m above sea level (asl) in the western part of Mt. Chiri in Korea. Trees larger than 2.5 cm DBH were inventoried in 3 to 8 $20m{\times}20m$ quadrats in each study site. Stand ages were estimated based on the ages of Pinus densiflora Siebold & Zucc. and Abies koreana Wilson, and used to analyze the changes in species composition and stand structure including diameter and height distributions. Species composition was changed along altitudinal gradients as P. densiflora dominated stands at 400 m asl while A. koreana dominated stands at 1,300 m asl. Major species of Quercus also changed along altitudinal gradients as Quercus variabilis Blume at 400 m asl, Quercus serrata Thunb. ex Murray at 800 m asl, and Quercus mongolica Fisch. ex Ledeb. at higher than 1,000 m asl. The diameter distribution did not show significant differences among stands of different altitudes. However, the height distributions of upper crown layers were significantly different among stands at below and above 1,000 m as) (P < 0.0001). Trees taller than 20 m rarely appeared in stands over 1,000 m asl. P. densiflora dominant stands at 400 m asl developed two clumped age groups as one in 30-40 ages and the other around 70 years old. Q. serrata dominant stands at 800 m asl, Q. mongolica dominant stands at 1,300 m asl and A. koreana dominant stands at 1,300 m asl were estimated to be around 30, 70, and over 140 years old after major disturbances, respectively. The diameter distribution with age structure indicated that P. densiflora at 1,300 m asl might be replaced by Q. mongolica, and Q. mongolica might be replaced by A. koreana and Pinus koraiensis later. A. koreana dominant stand seemed to stay its dominance quite long if the large disturbance would be absent.

• Journal of Korean Society of Forest Science
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• v.43 no.1
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• pp.35-38
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• 1979

The solubility variations of Abies koreana Wilson wood and their correlations ammong the factors which effect the extraction were investigated. In hot water solubility for 10 hours, extracted contents were 2.33% in heart wood, 12.30% in sapwood. In base solubility (here, used NaOH), the solubility content was 8.23% only for 1 hour. In organo-soluble fractions, there was not any variation between the content 4.00% for 1 hour and 4.44% for 10 hours, about the temperature effect, in the neutral solvent, at temperature $25{\pm}3^{\circ}C$, $50{\pm}3^{\circ}C$ and $97{\pm}3^{\circ}C$ and the solubility contents were 2.73%, 3.29%, 7.32% respectably. In the pH variations, initinal pH of solution, 6.5 became as low 5.4 after 10 hours extraction. Generally, the correlation coefficients between solubility and hour, solubility and temperature, solubilities' pH and hours, solubility and part, were r=0.890, r=0.986, r=-0.955, r=0.840 respectably. It is suggested that the most serious factor of the extraction in this material is the temperature.

• Journal of Astronomy and Space Sciences
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• v.26 no.2
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• pp.141-156
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• 2009

Through the photometric observations of the near-contact binary, XZ CMi, new BV light curves were secured and seven times of minimum light were determined. An intensive period study with all published timings, including ours, confirms that the period of XZ CMi has varied in a cyclic period variation superposed on a secular period decrease over last 70 years. Assuming the cyclic change of period to occur by a light-time effect due to a third-body, the light-time orbit with a semi-amplitude of 0.0056d, a period of 29y and an eccentricity of 0.71 was calculated. The observed secular period decrease of $-5.26{\times}10^{-11}d/P$ was interpreted as a result of simultaneous occurrence of both a period decrease of $-8.20{\times}10^{-11}d/P$ by angular momentum loss (AML) due to a magnetic braking stellar wind and a period increase of $2.94{\times}10^{-11}d/P$ by a mass transfer from the less massive secondary to the primary components in the system. In this line the decreasing rate of period due to AML is about 3 times larger than the increasing one by a mass transfer in their absolute values. The latter implies a mass transfer of $\dot{M}_s=3.21{\times}10^{-8}M_{\odot}y^{-1}$ from the less massive secondary to the primary. The BV light curves with the latest Wilson-Devinney binary code were analyzed for two separate models of 8200K and 7000K as the photospheric temperature of the primary component. Both models confirm that XZ CMi is truly a near-contact binary with a less massive secondary completely filling Roche lobe and a primary inside the inner Roche lobe and there is a third-light corresponding to about 15-17% of the total system light. However, the third-light source can not be the same as the third-body suggested from the period study. At the present, however, we can not determine which one between two models is better fitted to the observations because of a negligible difference of $\sum(O-C)^2$ between them. The diversity of mass ratios, with which previous investigators were in disagreement, still remains to be one of unsolved problems in XZ CMi system. Spectroscopic observations for a radial velocity curve and high-resolution spectra as well as a high-precision photometry are needed to resolve some of remaining problems.

• The Korean Journal of Pesticide Science
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• v.5 no.3
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• pp.12-17
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• 2001

A new 2,3-dihydro-2,3,4,6,7-pentamethylbenzofuran-5-yl substituents in 5-benzofuryl-2-[1-(alkoxyimine) alkyl]-3-hydroxycyclohex-2-en-1-ones were found to have herbicidal activity against rice plant (Oryza sativa L.) and barnyard grass (Echinochloa crus-galli) under submerged conditions. The structure activity. relationships (SARs) on the herbicidal activity of $R_1\;and\;R_2$ on the azomethine bond of 2,3-dihydro-2,3,4,6,7-pentamethylbenzofuran-5-yl subsituents were analysized. The conditions of the selective herbicide activity between rice plant (seed) and barnyard grass from the basis on the analysized SARs are assumed that the $R_2$ group of ethyl substituent ($R_1$ ) should have optimal asymmetry parameter, $(L/B_1)_{opt.}=3.96{\AA}$. And also, the $R_2$ groups consist of $C_1{\sim}C_3$ and unsaturated group such as 3-chloro-2-propenyl group was contribution to the herbicide activity.

• Korean journal of applied entomology
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• v.7
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• pp.33-37
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• 1969

This experiment was conducted to investigate the vriabibities of the pupal weight and the number of eggs in the ovary of the fall webworm, Hyphantria cunea Drury. collected from the seven different host plants in the field. The correlation between the pupal weight and the number of eggs in the ovary was studied in connection with the species of the host plants. The results obtained were as follows. I) The pupal eight was varied with the species of the host plants and sexes. The order of average female pupal weight was Populus euramericanal Guinier(206.6 mg). Juglans mandshurica Max. (J97.8 mg). Platanus orientalis L. (182.4 mg). Acer neugndo L. (172.2 mg). Taxodium distichum Rich. (172.1 mg). Salix babylonica L. (128.8 mg) and Prunus serrulata var. spontanea (Max). Wilson (103.4 mg). and of the average male pupal weight. T. distichum (125.2 mg). P. orientalis (123.5mg). J. mandshurica (114.4 mg). A. negundo (109.5 mg). Peuramericana (106.3mg). S. babylonica (94.3 mg). and P. serrulata var. spontanea(74.6 mg). The weight of female pupae was greater than that of male pupae in all case. 2) The unmber of eggs in the ovary was also vaied with the species of the host plants. The order of the average number of eggs in the ovary was P. euramericana(1331.1). J. mandshurica(I239.9). T. disichum (1237.0). A. negundo (1186.9). P. orientalis (1145.5), S. babylonica (800.0) and P. serrulata var. spontanea (641.5). 3) The number of eggs in the ovary for all the host plants tested was highly correlated with the pupal weight.

• Korean Journal of Plant Resources
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• v.30 no.2
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• pp.167-175
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• 2017

We conducted a total of 28 surveys from March to October 2016 in Gayasan National Park, to identify threatened plants for climate change, as well as for the effective management of biological organisms and resources against climate changes in Korea. Regarding threatened plants for climate change, we identified a total of 39 taxa, with 11 northern, 2 southern, and 26 taxa of concern. Among these taxa, 33 were identified as wild species. The species threatened by climate change located in the subalpine regions of Gayasan National Park were Abies holophylla Maxim., Abies koreana Wilson, Pinus koraiensis Siebold & Zucc., Betula ermanii Cham., Berberis amurensis Rupr., Rhododendron tschonoskii Maxim., Vaccinium hirtum var. koreanum (Nakai) Kitam., Primula modesta var. hannasanensis T.Yamaz., Trientalis europaea var. arctica (Fisch.) Ledeb., Thymus quinquecostatus Celak., Parasenecio firmus (Kom.) Y.L.Chen, and Lilium cernuum Kom. These species are expected to be particularly vulnerable to the effects of global warming, since they were confirmed to have a very narrow vertical distribution range. Moreover, although the following species are not included in the list of plants threatened by climate change, it is assumed that the endemic species that grow at the summit, and Grade V floristics special plants, such as Pedicularis hallaisanensis Hurus., Allium thunbergii var. deltoides (S.O.Yu, S.Lee & W.Lee) H.J.Choi & B.U.Oh, Heloniopsis tubiflora Fuse, N.S.Lee & M.N. Tamura, Aletris glabra Bureau & Franch, and Gymnadenia cucullata (L.) Rich., will also be extremely vulnerable to climate change. Therefore, we believe that measures for the conservation of these species are urgently needed, and also that the definition of species threatened by climate change should be broadened to include more objective and valid taxa through the long-term monitoring of species distributed around the summit area.

• Molecules and Cells
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• v.25 no.1
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• pp.30-42
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• 2008

The disease-specific (dsp) region and the hypersensitive response and pathogenicity (hrp) genes, including the hrpW, $hrpN_{Ep}$, and hrpC operons have previously been sequenced in Erwinia pyrifoliae WT3 [Shrestha et al. (2005a)]. In this study, the remaining hrp genes, including the hrpC, hrpA, hrpS, hrpXY, hrpL and hrpJ operons, were determined. The hrp genes cluster (ca. 38 kb) was comprised of eight transcriptional units and contained nine hrc (hrp conserved) genes. The genetic organization of the hrp/hrc genes and their orientation for the transcriptions were also similar to and collinear with those of E. amylovora, showing ${\geq}80%$ homologies. However, ORFU1 and ORFU2 of unknown functions, present between the hrpA and hrpS operons of E. amylovora, were absent in E. pyrifoliae. To determine the HR active domains, several proteins were prepared from truncated fragments of the N-terminal and the C-terminal regions of $HrpN_{Ep}$ protein of E. pyrifoliae. The proteins prepared from the N-terminal region elicited HR, but not from those of the C-terminal region indicating that HR active domains are located in only N-terminal region of the $HrpN_{Ep}$ protein. Two synthetic oligopeptides produced HR on tobacco confirming presence of two HR active domains in the $HrpN_{Ep}$. The HR positive N-terminal fragment ($HN{\Delta}C187$) was further narrowed down by deleting C-terminal amino acids and internal amino acids to investigate whether amino acid insertion region have role in faster and stronger HR activity in $HrpN_{Ep}$ than $HrpN_{Ea}$. The $HrpN_{Ep}$ mutant proteins $HN{\Delta}C187$ (D1AIR), $HN{\Delta}C187$ (D2AIR) and $HN{\Delta}C187$ (DM41) retained similar HR activation to that of wild-type $HrpN_{Ep}$. However, the $HrpN_{Ep}$ mutant protein $HN{\Delta}C187$ (D3AIR) lacking third amino acid insertion region (102 to 113 aa) reduced HR when compared to that of wild-type $HrpN_{Ep}$. Reduction in HR elicitation could not be observed when single amino acids at different positions were substituted at third amino acids insertion region. But, substitution of amino acids at L103R, L106K and L110R showed reduction in HR activity on tobacco suggesting their importance in activation of HR faster in the $HrpN_{Ep}$ although it requires further detailed analysis.