• Journal of Bio-Environment Control
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• v.8 no.2
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• pp.83-89
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• 1999

Butterhead lettuce was grown hydroponically in a plant factory during summer season. To decrease the occurrence of tipburn and increase productivity, optimum cultivars, substrates, gully slope and height, and the amount of irrigation were evaluated in this experiment. Cultivars ‘Rex’ and ‘Flandria’ showed higher productivity with less tipburn as compared to the others in spite of lower growth rates and appeared to be suitable cultivars during summer season. Cocopeat showed high productivity due to superior physio-chemical characteristics. Appropriate gully slope which makes nutrient solution easy to flow was shown to be 1 to 2%. The amount of irrigation was appropriate at 2$\ell$/gully. Higher growth of the butterhead lettuce observed when the bed was at a lower position. Low bed was thought to be good for lettuce growth with proper humidity and average temperatures.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.454-464
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• 1986

To find main factors to affect tobacco culture and quality, NC 2326 (Nicotiana tabacum L.) was cultivated in Korea and in the United States under different plant density, fertilization, mulching and curing. Among the chemical characteristics of the both experimental soils, the organic matters were similar concentration in both locations but effective phosphorous contents were higher in Oxford in the United States. Plant height, length and width of the largest leaf, leaf thickness, and midrib ratios were larger in Oxford than in Suwon in Korea. Also they were larger in non mulching system than in mulching system. But the total numbers of the leaves were decreased in non mulching system. The content of nicotine was higher in the plant grown in Suwon than in Oxford. The concentrations of nicotine and sugar tend to increase in mulching system comparing of non mulching system. During the growing, the concentration of non-volatile organic acids was higher in Suwon, while it was lower in cured leaf produced in Suwon. Also the contents of total fatty acids were lower in the harvested leaf grown in Suwon, but not in cured tobacco. Forty three compounds identified among the volatile oils from these experimental samples were quantified. The concentrations of the major components related to the tobacco flavour such as damascone, damascenone, solanone, nor-solanadione, and megastigmatrienones were higher in the cured tobacco produced in Oxford rather than in Suwon.

• Journal of Radiation Protection and Research
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• v.21 no.1
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• pp.51-58
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• 1996

Underground migration of $^{54}Mn,\;^{60}Co,\;^{85}Sr\;and\;^{137}Cs$ in paddy and upland conditions was studied through two years' greenhouse experiment. At early and late growth stages of rice, soybean, Chinese cabbage and radish, a mixed solution of the radionuclides was applied to the water or soil surfaces of the culture boxes filled with an acidic loamy-sandy soil for the upper 20cm. Soil was sampled in layers upto $15{\sim}20cm$ down after harvest. Soil concentrations of the radionuclides decreased exponentially with increasing soil depth and more than 80% of the radioactivities remained in top $3{\sim}4cm$. The mobility of the radionuclides decreased in the order of $^{85}Sr>^{54}Mn>^{60}Co{\geq}^{137}Cs$. Downward migrations of the radionuclides were the greatest in rice soil and the lowest in soybean soil which was fertilized with the least amount of N, P and K. Differences in depth profiles between two application times indicate that the amount of daily migration from $0{\sim}1cm$ layer to the lower area decreases with increasing time after deposition. By a simultaneous addition of KCl and lime following the earlier application, downward migration in soybean, Chinese cabbage and radish soils changed little or retarded more or less but that in rice soil accelerated a little.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.793-797
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• 2010

The investigations were conducted to improve the physical properties by analyzing physico-chemical properties on the different soil families of textures at 20 upland fields located in the parts of Gyengsangbuk-do area. Soil physico-chemical properties were analyzed for bulk density, hardness, porosity, moisture, pH, EC and organic mater by soil depth on the different soil families of textures. Bulk density distributions were higher than 1.2 Mg $m^{-3}$ in the optimum range. Hardness distributions were lower than 20 mm in the optimum range. Therefore, the physical properties of upland soil was deteriorated. Correlation coefficient of bulk density with hardness and organic mater were higher significantly, that was positive and negative, respectively. The soil hardness had the greatest distribution degree to the crop yield and bulk density and organic matter followed. Conclusively, To improve the physical properties of upland soil was more effective to fertilizing organic matter than other ways.

• Korean Journal of Environment and Ecology
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• v.8 no.2
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• pp.81-92
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• 1995

The flora of the Chuwangsan National Park was surveyed. The field works was done for three times from February to October, 1994. The total number of vascular plants in this area were surveyed as 433 taxa ; 94 families, 260 genera, 365 species, 60 varieties, 2 subspecies, 5 formas, and 1 cultivars. The twenty seven taxa which were artificially planted could be found at the temple and abandoned cultivated areas. The population of Jeffersonia dubia Benth, one of the rare and endangered plants in Korea, were surveyed and mapped for an ecological monitorings in the future. Since this population is restrictly located in the vicinity of the mountain trails, the protection measures should be urgently needed in the future.

• Korean Journal of Environment and Ecology
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• v.13 no.3
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• pp.288-294
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• 1999

경상북도 안동 사문암지역 및 부근의 화강암지역에 분포하는 암석, 토양 및 식물체에 함유되어 있는 원소의 농도를 조사한 결과는 다음과 같다. 본 조사지역에분포하는 사문암에 함유되어 있는 주요 전이원소 함량(Ni 1.164ppm. Cr 366ppm. Co 109ppm. Fe 7.48%) 및 다른 대부분의 전이원소(Sc, Mn, Cu)도 화강암보다 높았으며 우리나라 efms 지역의 사문암에 함유되어 있는 농도와 비교하여 볼 때 매우 유사한 경향을 보이고 있다. 사문아토양의 경우 암석풍화토양 및 산림토양 모두 화강암토양에 비해 Ni, Co, Cr, Fe, Sc, Mn, Cu, Mg, Zn 농도가 높았으며 Pb는 반대의 경향을 나타내었다. 토양내 원소 함량은 이들의 모암에 함유되어 있는 원소 함량의 변화와 일치하고 있으며 같은 모암인 경우 산림식생의 영향에 따라 면 원소들의 차이가 다소 나타났다. 식물체 내 원소의 농도는 토양의 농도에 비해 모두 낮았다. 참억새, 쑥, 소나무에 함유되어 있는 원소별 평균 농도는 모두 동일종간 대부분의 전이원소(Ni, Co, Cr, Fe) 및 As 농도가 화강암토양에 비해 사문암토양에서 더높았다 사문암토양에서 생육하는 식물체 3종 모두 대부분의 원소(Ni, Co, Cr. As, Sc, Fe) 함랴이 지하부에서 더 높았으며 Zn과 Mo는 지상부와 지하부의 농도 차이가 크게 나타나지 않았다 화강암토양에서 생육하는 식물체의 경우 원소별 지상부 및 지하부의 농도차이는 사문암토양에 비해 크지 않았다.

• Korean Journal of Agricultural Science
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• v.34 no.2
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• pp.119-123
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• 2007

Germination ratio on the 300 collected genetic resources showed 80 to 100 percentage, but those of some accessions were very low as below 30 percentage. Early growth phase of most of these lines were very poor while some collected lines were very vigor. Range of stem height showed from 150 to 199cm, but that of some accessions showed below 100cm as five percentage and some of them was over 250cm as eight percentage. Number of tillers per plant appeared less one but some collected lines have two to three tillers per plant. In days to tasseling, some accessions showed more four per plant. Ear length of these accession showed above 60 percentage as 11 to 15cm, while that of some collected lines showed over 10 percentage as 16 to 20cm.

• The Korean Journal of Ecology
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• v.17 no.3
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• pp.333-344
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• 1994

Community structure and habitat characteristics of Acer mono stands were studied in Mt. Giri $(127{\circ}35'E.,\;35{\circ}18'N)$ and Mt. $Baekun(127{\circ}38'E.,\;35{\circ}05'N)$. The vegetation was investigated by the Braun-Blanquet's phytosociological method. Distribution of Acev mono was most abundant on eastern and western slopes in valley side. The community structure was composed of 4 layers and average number of species appeared in each quadrat was 24. Habitats were almost covered with exposed rocks and the surface soil was classified to clay loam. The isothermal date lines of Mt. Giri and Baekun were 130 and 120 days, respectively, which is the number of days with mean daily minimum temperature below zero during the year. The daily range of temperature was compared at 4 regions during sap extraction.

• Korean Journal of Environment and Ecology
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• v.21 no.1
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• pp.74-81
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• 2007

This study investigated the growth pattern and species composition by landform and seaside distribution to evaluate the basic community structure and topographical distribution of the Peucedanum japonicum Thunb. community group in Korea. The appearing plants with the Peucedanum japonicum Thunb. were a total 170 taxa belonging to 130 genera and to 57 families, and the species number by families was the most in Compositae of 30 taxa. The frequency of appearing plants was the highest in the Aster spathulifolius Max.(54.1%), and the east and west seasides were the highest in the Aster spathulifolius Max. and south seaside was the highest in the Miscanthus sinensis Ander.. The ratio of common plants among seasides was the highest between the west and south seasides of 35.6% with 47 taxa. The distribution landforms of the Peucedanum japonicum Thunb. was a $17.4^{\circ}$ slope of the unevenness landform, vertical joint, horizontal joint, blockfield, planation surfaces and the rocky seaside of the sea cliff. The distribution among landforms was the greatest in the rocky seaside of the 61 regions. The sociability on growing pattern was the highest in the 3 sociability rank of 54.6% with the 83 region.

• Korean Journal of Plant Resources
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• v.15 no.2
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• pp.96-106
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• 2002

Five major naturally populated habitats around the Mt. Daeduk, Gangwon province for wild Chuiangne (Pyrus ussuriensis var. acidula) are mostly located on the southeast side of the mountains at 1,216-1,306ｍ in altitude at sea level and are in very good sunney areas. The total of 96 taxa dividing into 40 families, 79 genera 84 species and 12 varieties have in these areas. Most of these plants are heliophytes, which love sunshine, Compositaes such as Artemisia stolonifera, Synurus deltoides, or Rosaceaes like Potentilla fragarioides var. major are also shown. These areas have been unknown destroyed, so it is possibly thought the second transition has been progressed. The index of species diversity of plant groups in these areas is 4.715-5.270 based on the Shannon-Wiener's method. The wild Chuiangne with 34.15％, which are 5-10㎝ DBH, have been found in habitats. The vegetation around the habitats must be managed by the man in order to keep sound growth of the wild Chuiangne.