• Korean Journal of Medicinal Crop Science
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• v.16 no.6
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• pp.434-438
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• 2008

To selection of optimal shading material, two-year-old ginseng (Panax ginseng C. A. Meyer) of new cultivar, 'Cheonpoong' (CP), and native species 'Hwangsookjong' (HS) were cultured under three kinds of shading materials such as three-layered blue and a one-layered black PE (polyethylene) net (TBSB), blue PE sheet (BS), and aluminium coated PE sheet (AS) in imperfectly drained paddy soil. Growth characteristics, yield and ginsenoside contents were investigated under three shading materials. Yield and ginsenoside contents of ginseng were distinctly affected by intensity and quality of sunlight penetrated through shading materials. Light transmission ratio, air and soil temperature according to shading materials were higher in order of BS, AS, and TBSB. However, ratio of aerial phase and porosity of the soil were higher in order of AS, BS, and TBSB, respectively. There was no significantly difference in the ratio of rusty colored root by shading materials. CP showed higher stem length, leaf area, and root weight than that of HS, while the former showed distinctly lower discolored leaf ratio than that the other. Eight kinds of ginsenosides content of CP were higher than that of HS in $Rg_1$, Re, Rf, $Rb_1$ and Rc except $Rg_2$, $Rb_2$, and $Rb_3$. Total ginsenoside contents of CP was distinctly higher than that of HS. Total ginsenoside contents as affected by shading materials was higher in order of BS, TBSB, and AS in CP, while TBSB, BS, and AS in HS.

• Journal of the Mineralogical Society of Korea
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• v.21 no.4
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• pp.331-339
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• 2008

In the upstream of Nakdong river in Bonghwa-gun, Gyeongsangbuk-do, certain areas of riverside were found to be covered by weathered mine tailings which were assumed to be migrated and deposited by flood. This study was conducted to investigate the formation and characteristics of the secondary minerals from tailings and related leaching behavior of heavy metals in the severely weathered tailing deposits by river waters. Quartz, feldspar, micas, chlorite, hornblende, talc, pyroxene (johannsenite), pyrite, and calcite were identified as primary minerals by XRD. Kaolinite can be formed by the weathering of tailings, but considering the short period of weathering time, kaolinite in the deposits is considered to be from unweathered tailings or moved from soils. The secondary minerals such as goethite, gypsum, basanite, and jarosite were also identified. The formation of the secondary minerals was affected by the species of primary minerals and pH conditions. The weathering of pyrite produced sulfate minerals such as gypsum, basanite, jarosite, and also goethite. Mn oxide was also identified by SEM, coated on the primary minerals such as quartz. This Mn oxide was poorly crystalline and thought to be the weathering product of johannsenite (Mn-pyroxene). The Fe and Mn oxides are the main minerals determining the brown/red and black colors of weathered tailings. EDS results showed that those oxides contain high concentrations of Pb, Zn, and As, indicating that, in the river, the formation of Fe and Mn oxides can control the behavior and leaching of heavy metals by co-precipitation or adsorption.

• Microbiology and Biotechnology Letters
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• v.15 no.2
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• pp.129-134
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• 1987

Aspergillus sp. (MK-24) producing a biological active substance that inhibited the venom proteinase activity was isolated from soil. The substance also inhibited the activity of trypsin and coagulation of blood, but did not inhibit papain, $\alpha$-chymotrypsin and pepsin. The substance was partially purified from culture filtrate by precipitaion with acetone, and by chromatography of DEAE-Sepadex A-50 column and Amberlite IRC-50 ion exchange. The inhibitory substance was stable in the wide pH range from 2.0 to 12.0 at 37$^{\circ}C$, but not stable at $65^{\circ}C$ in the alkaline pH. Only 12% of the activity was decreased by the heat treatment at 10$0^{\circ}C$ for two hours. The inhibition on venom proteinase (Agkistrodon bromohoffi brevicaudus) was a mixed type. The inhibitory activity depended on the preincubation time and completely depressed by cupric, zinc and cobalt ions. The inhibition on the venom proteinase was appeared strongly on casein but not on ovalbumin or hemoglobin as a substrate.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.4
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• pp.438-444
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• 2002

The purpose of this study is screening of microfloras involved in hydrolysis of sea tangle (Laminaria japonica) and sea mustard ( Undaria pinnatifida), This is a part of studies on the hydrolysis of seaweed using microorganisms. General process is difficult to extract of the useful constituent parts as intercellular mucilage, storage polysaccharide and mineral from seafood. It was screening to thirty-three microflora samples as destructed of tissue in sea tangle and sea mustard to about two hundred microflora samples from mountain, rice field, dry field, sea, seaside and fish market etc. in the neighborhood of Yeosu. Sufficient results of the naked eye observation were obtained at eight microflora samples as a feces of bull, a decayed pine tree, a soil of dry field, the mud of the banks in a rice Held, the water of a ditch in a rice Held, the weed of the banks in a rice field, the water in a rice field and leaved in the air, And the value of chemical analysis of the sample is much better in comparison with control. Accordingly, the hydrolysis of seaweed using microorganisms in the inside of these microflora samples can possibility.

• Korean Journal of Plant Tissue Culture
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• v.26 no.2
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• pp.127-132
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• 1999

Protoplasts were isolated from the leaf mesophyll tissue of in vitro 4-weeks-old Arabidopsis thaliana and cultured in MS liquid medium supplemented with 2.0 mg/L NAA, 0.5 mg/L BAP and 9% mannitol in the dark at $25^{\circ}C$. When protoplast-derived microcolonies were dehydrated, the frequency of callus induction enhanced approximately 7-fold higher compared with non-dehydrated microcolonies in CP medium. Fifty callus lines were selected from dehydrated microcolonies. Shoots were efficiently initiated from the green spots of the selected shoot forming calli cultured on MS regeneration medium supplemented with 0.05 mg/L IAA, 7.0 mg/L 2-iP and 30 g/L sucrose under continous illumination for 4 weeks. Shoot regeneration frequencies (calli regenerating at least one shoot) were 3.5%~56%. Histological observations of shoot forming callus revealed that tracheary elements initiated from inner compact cells, and that meristemoids developed to shoot primordia and shoots. Roots were induced from these regenerating shoots on MS medium without phytohormones. These regenerants were successfully transplanted into potting soil. Morphological characterization of 50 protoplast-derived plants showed that the frequency of normal type was 78%.

• Journal of Korean Society of Forest Science
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• v.90 no.5
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• pp.632-642
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• 2001

Fauna, especially Carabidae (Coleoptera), on the floor of Pinus densiflora forests was investigated at five plantations and was compared with that in a mixed natural forest of pine and deciduous trees. There was little difference in the ground beetle fauna among the five P. densiflora plantations, and the bio-diversity of soil layer fauna was poor in all the pine plantations. Individual numbers of the beetles belonging to the genus Synuchus with increasing the infestation rate of the pine needle gall-midge (Thecodiplosis japonensis). These beetles seem to be important predators of the gall-midge. Comparing to the mixed forest, the number of higher taxa and the numbers of genera and species of Carabidae were all small in the pine forests. And especially, most flightless species were found only in the mixed forest. Thus, it is concluded that many species of Carabidae which had been lost from the lower mountainous areas of Korea have not recovered yet in the pine forests.

• Journal of Korea Foresty Energy
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• v.22 no.2
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• pp.44-53
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• 2003

This study was conducted to develop new fertilizers which can be applied to various environmental conditions. Fertilizers with different levels of nitrogen, phosphorus and potassium, and different types and amount of combined fertilizers were used on 1-1 seedlings of Pinus densiflora, Larix leptolepis, Quercus acutissima, and Betula platyphylla var. japonica. Biomass, specific leaf area (SLA) and chlorophyll content of foliage were measured. Biomass of foliage, shoot, and root showed no differences among fertilization treatments. Biomass of double treatments of solid-combination fertilizer and UF combination fertilizer increased whereas those of triple treatments decreased. SLA ($\textrm{cm}^2$/g) of P. densiflora fo. the 6:4:1 treatment and L. leptolepis for the 3:4:1 treatment showed the highest with 59.2 and 110.0, respectively, but those of Q. arutissima and B. platyphylla var. japonica for the control showed the higher than other treatments with 207.5 and 202.0, respectively. Chlorophyll contents (mg/g) in the foliage of P. densiflora and L. leptolepis fertilized with the 6:4:1 treatment were 0.222 and 0.127, respectively, and these contents were higher than those of the 3:4:1 treatment with 0.211 and 0.082, respectively. These results suggested that the increased nitrogen fertilization had an effort on increase of chlorophyll contents.

• Korean Journal of Environment and Ecology
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• v.6 no.1
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• pp.25-43
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• 1992

A survey of Orimok, Yongsil and Donnaeko area forest in Mt. Halla. was conducted using 71 sample plots of 500$m^2$ size. In the analysis of -actual vegetation, Carpinus tschonoskii and C. laxiflora community covered 53.7%, Quercus grosseserrata - Q. serrata community 25.8%, Pinus densiflora community 8.3%, Abies koreana community 4.5% and these communities covered 92.2% of Mt. Halla forest. The degree of 8, 9 and 10 in human disturbance of vegetation covered 64.5, 28.6 and 6.9% respectively. The classification by TWINSPAN and DCA ordination were applied to the study area in order to classify them into several groups based on woody plants and environmental variables. By two techniques, the plant community were divided into several groups by the aspect and altitude. The dividing groups are C. tschonoskii community, C. tschonoskii - Q. serrata community, P. densiflora - C. tschonoskii community, P. densiflora - C. laxiflora community, C. laxiflora community, C. laxifrora - Daphniphyllum macropodum - Eurya japonica community, P. densiflora community. The successional trends of tree species by both techniques seem to be from P. densiflora. Sorbus alnifolia through Q. serrata. Maackia faurier to C. tsihonoskii in Orimok and Yongsil area and from P. densifiora to C. laxiflora in Donnaeko area. There was no difference between the stand scores of. DCA and environmental variables.

• Journal of the Korea Concrete Institute
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• v.22 no.2
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• pp.219-228
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• 2010

It has been well known that concrete structures exposed to acid and sulfate environments such as sewer, sewage and wastewater, soil, groundwater, and seawater etc. show significant decrease in their durability due to chemical attack. Such deleterious acid and sulfate attacks lead to expansion and cracking in concrete, and thus, eventually result in damage to concrete matrix by forming expansive hydration products due to the reaction between portland cement hydration products and acid and sulfate ions. Objectives of this experimental research are to investigate the effect of mineral admixtures on the resistance to acid and sulfate attack in concrete and to suggest high-resistance concrete mix against acid and sulfate attack. For this purpose, concretes specimens with three types of cement (ordinary portland cement (OPC), binary blended cement (BBC), and ternary blended cement (TBC) composed of different types and proportions of admixtures) were prepared at water-biner ratios of 32% and 43%. The concrete specimens were immersed in fresh water, 5% sulfuric acid, 10% sodium sulfate, and 10% magnesium sulfate solutions for 28, 56, 91, 182, and 365 days, respectively. To evaluate the resistance to acid and sulfate for concrete specimens, visual appearance changes were observed and compressive strength ratios and mass change ratios were measured. It was observed from the test results that the resistance against sulfuric acid and sodium sulfate solutions of the concretes containing mineral admixtures were much better than that of OPC concrete, but in the case of magnesium sulfate solution the concretes containing mineral admixtures was less resistant than OPC concrete due to formation of magnesium silicate hydrate (M-S-H) which is non-cementitious.

• Korean Journal of Plant Resources
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• v.28 no.1
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• pp.64-78
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• 2015

The environmental characteristics of Astilboides tabularis were investigated to compile basic data for conservation and restoration. Natural habitats, according to investigations, were mostly located on the slopes of mountains facing north at an altitude of 432 m to 1,413 m above sea level with angles of inclination ranging from 16 degree to 49.5 degree. A total of 246 vascular plant taxa were identified from 12 quadrats in 11 habitats. The importance value of Astilboides tabularis is 20.40%, and 6 highly ranked species such as Dryopteris crassirhizoma (4.56%), Rodgersia podophylla (3.72%), Astilbe rubra (2.81%), Carex siderosticta (2.67%), Ainsliaea acerifolia (2.65%), and Meehania urticifolia (2.46%) are considered to be an affinity with Astilboides tabularis in their habitats. Average species diversity was 1.23, dominance and evenness were found to be 0.11 and 0.86, respectively. The litter depth above the soil surface was 2 to 10 cm, and soil depth was 20.8 to 67.5 cm. The soil texture of habitats were divided three types such as loam, silt loam, and sandy loam. The soil pH was 5.63 to 7.74, and the organic matter and nitrogen contents were ranged from 8.88 to 42.55%, and 1.40 to 6.58 mg/g, respectively.