• Korean Journal of Environmental Biology
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• v.30 no.3
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• pp.272-279
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• 2012

This was the second study on the ecological characteristics of the epiphytes on seagrass leaf. The objective of this study was to understand the variation of epiphytes on seagrass leaf depending on the change of physico-chemical factors such as salinity, nutrients, and etc. This study showed the four results. 1) The eelgrass growth was influenced by water temperature, suggesting the positive correlation between eelgrass growth and water temperature. 2) The epiphytes growth on seagrass leaves did not show the correlation with water temperature, but negatively correlated with salinity. 3) The eelgrass growth decreased when the concentraion of nitrogen increased. 4) However, loads of epiphytes increased when the concentration of total nitogen (TN), nitrate ($NO_3^-$), and nitrite ($NO_2^-$) were high. This increase of epiphytes growth could be suggested in the cause-effect pathway of nutrient enrichment leading to seagrasses loss.

• The Korean Journal of Ecology
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• v.14 no.4
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• pp.379-398
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• 1991

In order to investigate the ecotypic variations of pulsatilla koreana nakai distributed in korea, 8 local populations of the plant were selected in accordance with latitude and compared on the differences of leaf shape, elongstion, stomatal distribution and dhlorophyll content. The incised angle of the plant is 38。32' in cheju, showing a great difference as compared with 23。77'-30。 32' of the other sites. as to the incised rate, mt. togyu and cheju representsed relatively high values of 49.04% and 48.21% the parted leaved individuals were only observed along the warm current coastal area including cheju, sokcho and sunchon and were 54(62.8%), 2(2.5%) and 3(3.3%) in the sites, respectively. Especially, the individuals consisting of only parted learves were 5(5.8%) in cheju alone and none of the other sites showed such individuals at all. So p. cernua distributed in cheju and p. koreana in inland area can be considered to beecotypic variations of the same species from the upper investigations. According to the elongations of leaf and rachis, the local populations could be classified into 3 types, such as warm current coastal area type(cheju,sunchon and sokcho),southern inland area type(andong, chungju and mt. togyu)and central inland ara type(mt. komdan and hongchon). The dentate numbera of 39.80-43.73 in the warm current area were also different from those of 87% in mt.togyu and 15% in hongchon, while opposite leaflets account for 100% in the other sites. The content of chlorophyll ranged from 0.609 mg/g. d.w.(cheju)to 0.924 mg/g.d.w.(hongchon), showing an increasing trends as the latitudes grow higher. The number of stomata on the low epidermis is much larger than that on the upper epidermis in the whole area. But both aspects showed an increasing tendency, too as the latitude becomes higher.

• Korean Journal of Environmental Biology
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• v.24 no.4
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• pp.408-415
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• 2006

Serpentines soil have high values of magnesium and low values of calcium, and are usually deficient in N and P, but rich in iron, Ni, silicates. We investigated serpentine soil properties and measured the content of nutrient elements and heavy metals in shoots and root of plant species which were in common at serpentine and non-serpentine areas in Andong, Korea. The soils showed higher pH value above 6.9. The contents of Ni, Cr, Fe and Mg of serpentine soils exhibited 77, 27, 5.5 and 12.5 times more than in non-serpentine soils, respectively. The content of Na was almost same but K was two times higher in non-serpentine soil, compared with serpentine soil. The contents of nutrient element such as K, Ca, Na and P in serpentine plants did not show conspicuous differences with non-serpentine plants. On the other hand, the concentrations of Ni, Cr, Fe, Mg and Mg/Ca were very high in plant on serpentine area. The all plant species collected at the serpentine site were bodenvag plants, which are not restricted to a specific type of substrate. By the plant species and parts of plant tissues, the absorption levels and patterns showed high variation and were species-specific. Carex lanceolata, Lysimachia clethroides and Cynanchum paniculatum contained much chromium and Eupatorium chinense and C. paniculatum exhibited high contents of Ni. In leaf tissue, C. lanceolata, Rubus parvifolius, Festuca ovina, Quercus serrata, and L. clethroides took comparatively large amount of Cr in serpentine area. E. chinense contained large amount of Ni, Cr and Fe in a leaf tissue. The stem of Galium verum, Juniperus rigida included high amount of Cr, Ni and Fe. And C. paniculatum absorbed large amount of Ni and Cr in the stem.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.3
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• pp.51-59
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• 2004

Focusing on WBGT(Wet Bulb Globe Thermometer Index) according to the LAI(Leaf Area Index) variation of trees, this study verifies the effects of urban shade trees on the outdoor thermal environment. As for methodology, air$.$globe temperature, air humidity and WBGT were measured under three shade trees whose LAIs were 2.1, 4.0 and 8.2 respectively at midday(12:00-13:00) of 14 sunny days from the 4th through the 29th day of September 2003. Those factors were also measured at the unshaded areas and compared with the values of shaded areas. The measured site was paved with interlocking concrete bricks. The measurements were analyzed through the ANCOV A(Analysis of Covariance) and the regression routines of SPSS11 for windows (SPSS Inc., 2001). The major findings were as follows. 1. The direct correlation between WBGT and LAI was very low. On the contrary, the WBGT showed close correlation with air$.$globe temperature and air humidity, and the LAI also showed very close correlation with globe temperature. These results tell that dominant shading effect by the tree is on the screening of direct solar radiation which lower the globe temperature and WBGT consequently. 2. While the average globe temperatures and WBGT at unshadowed area were 40.4$^{\circ}C$ and 26.2$^{\circ}C$ respectively, the former under the shade tree with LAI 2.1, 4.0 and 8.2 were 34.5$^{\circ}C$, 32.6$^{\circ}C$ and 30.2$^{\circ}C$, and the latter were 24.6$^{\circ}C$, 24$^{\circ}C$ and 23.4$^{\circ}C$ respectively. 3. The relationship between LAI(x) and WBGT(y) can be presented with the following equation: y = 24.23+1.53 $e^{-x}$+0.36x $e^{-x}$+0.46 $x^2$ $e^{-x}$ ($R^2$ =.98) =.98)

• Journal of Ginseng Research
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• v.40 no.2
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• pp.176-184
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• 2016

Background: Wild ginseng, Panax ginseng Meyer, is an endangered species of medicinal plants. In the present study, we analyzed variations within the ribosomal DNA (rDNA) cluster to gain insight into the genetic diversity of the Oriental ginseng, P. ginseng, at artificial plant cultivation. Methods: The roots of wild P. ginseng plants were sampled from a nonprotected natural population of the Russian Far East. The slides were prepared from leaf tissues using the squash technique for cytogenetic analysis. The 18S rDNA sequences were cloned and sequenced. The distribution of nucleotide diversity, recombination events, and interspecific phylogenies for the total 18S rDNA sequence data set was also examined. Results: In mesophyll cells, mononucleolar nuclei were estimated to be dominant (75.7%), while the remaining nuclei contained two to four nucleoli. Among the analyzed 18S rDNA clones, 20% were identical to the 18S rDNA sequence of P. ginseng from Japan, and other clones differed in one to six substitutions. The nucleotide polymorphism was more expressed at the positions 440-640 bp, and distributed in variable regions, expansion segments, and conservative elements of core structure. The phylogenetic analysis confirmed conspecificity of ginseng plants cultivated in different regions, with two fixed mutations between P. ginseng and other species. Conclusion: This study identified the evidences of the intragenomic nucleotide polymorphism in the 18S rDNA sequences of P. ginseng. These data suggest that, in cultivated plants, the observed genome instability may influence the synthesis of biologically active compounds, which are widely used in traditional medicine.

• Journal of Korea Water Resources Association
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• v.46 no.9
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• pp.957-967
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• 2013

High turbidity submersion due to torrential downpour is one of the factors that influences the plant growth. This study is focused on analyzing the plant's growth rate for Salix species such as gracilisyla, koreensis, glandulosa when these trees are waterlogged. The length of shoots for this control group in the natural state is 33.4% (gracilisyla), 24.3% (koreensis), 23.9% (glandulosa), however, they stopped growing in submersion. Compared to the leaf number of Salix species of this control group in the natural state, 144.5% (gracilisyla), 77.3% (koreensis), 40.3% (glandulosa) in the natural state 30 days, in 30 days submersion, the number of leaves is zero except koreensis. In the results of this experiment, Salix species stopped growing quickly when submersed. This study concludes that it is necessary to plant eco-friendly plants around the slope of the reservoir and dam where flooding takes place frequently.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.4
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• pp.343-349
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• 1988

In order to get informations for breeding early barley cultivars, the thermosensitivity and low temperature growth ability about the breeding materials vernalized were tested at the high '||'&'||'amp; low temperature and field conditions. The temperature coefficient (Q10), ratio and thermosensitivity for plant height were various among cultivars versus temperature treatments. The early cultivars had greater Q10 values and insensitive responses to temperature changes. The Q10 and thermosensitivity for the time of flag leaf unfolding were various among cultivars, but the coefficient of variation in the thermosensitivity was greater, so the character would be more useful for investigating the varietal differences. The Q10 and thermosensitivity for plant height were not significantly correlated with Q10 and thermosensitivity for the time of flag leaf unfolding. The periods from heading to flowering were 2 to 4 days at the high temperature plot, but 1 to 11 days at the low temperature plot, showing much greater variations. In general the cultivars with greater difference of heading time between the high and low temperature plots were Suwon 218, SB 76588, Oweolbori, and Jogangbori, showing the sensitive thermophase and early heading.

• Korean Journal of Plant Resources
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• v.25 no.2
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• pp.257-270
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• 2012

The taxonomic relationship of 3 taxa in $Carex$ sect. $Siderostictae$ were revealed by morphological and molecular studies. The morphological characteristics of Korean $Carex$ siderosticta Hance, which is a type species of sect. $Siderostictae$, was first reviewed in comparison with previous records in order to identify the difference. Then the distribution map of this species was formulated through previous floral literatures and voucher specimens. Although the leaf shape which is represented by length/width ratio showed a great variation depending on habitat condition, the rhizome creeping patterns, the presence of hair on the surface leaf margin and perigynium were shown to be good diagnostic characters to define delimitation of species level. The results from molecular study supported $C.$ $ciliatomarginata$ Nakai should be ranked independently on species level.

• Korean Journal of Agricultural Science
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• v.24 no.2
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• pp.237-241
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• 1997

Including the check five tiller removal treatments; early tillering stages and active tillering stages, tasseling dates and flowering dates, were conducted for increasing the marketability of waxy maize hybrid with tillers. From resulting the experiments, the effects of ear size on the removal of tillers were largely appeared at treatment of early tillering stages, and next active tillering stages, tasseling dates and flowering dates. In analysis of variation ear length was shown the significance at 5% among treatments and ear diameter was shown significantly at 1%. Correlationships among components related to yield were positively shown between ear length and leaf width, ear diameter and leaf length. while was negativly shown between ear length and ear width.

• Journal of the Korean Society of Tobacco Science
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• v.6 no.1
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• pp.84-93
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• 1984

Six kinds of sugars (Maltose, Sucrose, Glucose, Fructose, Mannose and Lactose) and four kinds of organic acids (Malic, Tartaric, Lactic and Citric) were added by 2-10% for the former and 0.2-1.8% for the later in quantitatively to the inferior quality of Flue-cured leaf tobaccos, and treated at 135$^{\circ}C$ for 10 minutes to examine the effect on deliveries of tar and nicotine in smoke, variation of smoke pH and smoking taste. The results obtained are as follows. Tar and nicotine deliveries in smoke of tobacco show a great reduction with 5-6% addition of sugars. Reduction of nicotine delivery was to be 19% with addition of Glucose. Tar in smoke was, however, increased by 5-8% with 4% addition of Sucrose or Lactose. On the other hand, 4% addition of Glucose and Fructose gave 1 % reduction of tar delivery, but the reduction rate became to be small with increase of adding quantity. The smoking taste by the addition of Glucose and Fructose tobacco was found to be milder than by the other sugars. Tar and nicotine deliveries show a decreasing trend with the addition of organic acid, and Tartaric acid, among the organic acids described above, had greater effect than the other acids. 1% addition of Tartaric acid gaves 10-11% reduction in tar and nicotine delivery, and a fall of smoke pH, from 6.40 to 6.05, was found. Smoking taste by the addition of Lactic and Tartaric acid had milder than the others. And heat treatment for 10 minutes at $135^{\circ}C$ gave also better on smoking taste. The addition of mixture of sugars and organic acids, (Glucose 4%+Lactic acid 0.8% + Tartaric acid 0.2%) and then the successive heat treatment for 10 minutes at $135^{\circ}C$ improved greatly the quality of Fluecured leaf tobacco, and nicotine were reduced to 16-29%, and pH was changed from 6.46 to 6.14.