• Korean Journal of Environmental Agriculture
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• v.19 no.3
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• pp.213-217
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• 2000

In order to select more proper plants for phytoextraction at the heavy metal polluted areas, 11 species of non-edible plants were cultivated at the cadmium(Cd) and Lead(Pb) treated soils and analyzed the content of the absorbed Cd and Pb in each part of plants. Plants include three fibers(Linum usitatissimum, Cannabis sativa, Gossypium spp.), three flowers(Calendula officinalis, Rhododendron lateritium, Portulaca grandiflora), and five trees(Pinus thunbergii, Magnolia kobus, $Populus\;nigra\;{\times}\;P.$ maximowiczii, Euonymus japonica, Fraxinus rhynchophylla). Yield of tree species were higher than that of fiber and flower species. Cd and Pb were highly accumulated in root rather than leaves and stems. The Cd content of plants was in the order Portulaca grandiflora > Calendula officinalis > Gossypium spp. > Linum usitatissimum, Pb was Cannabis sativa > Linum usitatissimum > Fraxinus rhynchophylla. Total absorbed Cd by each plant was in the order $Populus\;nigra\;{\times}\;P.$ maximowiczii > Euonymus japonica > Rhododendron lateritium, but Pb was $Populus\;nigra\;{\times}\;P.$ maximowiczii > Rhododendron lateritium > Euonymus japonica. Total absorbed Cd and Pb contents in plants were negatively correlated with the residual Cd and Pb in the treated soils. It was estimated that $Populus\;nigra\;{\times}\;P.$ maximowiczii, Euonymus japonica, Fraxinus rhynchophylla, and Rhododendron lateritium were the most effective species for phytoextraction in the polluted area considering yield and heavy metal uptake.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.1
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• pp.25-30
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• 2006

This experiment was conducted to compare the fresh yield and dry matter yield, and nutritive values of whole crop barley treated with Urea (200 kg/ha, T2) and ammonium sulfate fertilizer as 200 kg/ha (T3), 300 kg/ha (T4) and 400 kg/ha (T5) at the Bae-Ho reclaimed tideland. Korea from 2003 to 2005. Salt contents of soil in the ammonium sulfate plots (T3, T4, T5) were lower than those of T2. The fresh yields of ammonium sulfate plots (T3, T4, T5) were higher than those of T2 as 62% (p>0.05), 41% (p>0.05) and 23% (p<0.05), respectively. The dry matter yield of T3, T4 and T5 (ammonium sulfate) was significantly (p<0.05) higher at 5,080 kg/ha, 4,667 ka/ha, 4,040 kg/ha, respectively. The total digestible nutrients (TDN) yield tends to have a similar result. Crude protein (CP) content was highest in T3 and CP trends to decrease as the level of ammonium sulfate was increased. Total digestible nutrient (TDN) were high in T3 and T4. The sodium content of T3 and T4 were lower than T2. Based on the study, it was more desirable to use ammonium sulfate (200 kg N/ha) rather than Urea as fertilizer on reclaimed land in terms of forage production and nutritive value.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.5
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• pp.401-407
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• 2006

This study was conducted to investigate the effect of onion cultivation under paddy and upland condition on the yield and storage of onion bulbs. In comparison of soil conditions, nitrogen, phosphate, potassium content and average temperature in upland condition were higher than those of paddy condition, but calcium, magnesium, sodium and water content in paddy condition were higher than those of upland condition. The growth of aerial part was better in upland cultivated condition. It showed that bulb formation in paddy cultivated condition was faster during in early growth stage, but was slower during in late growth stage. Average bulb size and weight were higher in upland cultivated condition, but dry weight per 100 g fresh weight and bulb hardness were higher in paddy cultivated condition. Sugar contents, inorganic compounds, nitrogen, phosphate and potassium content of onion were higher in upland cultivated condition, but calcium, magnesium and sodium content of onion were higher in paddy cultivated condition. In distribution of onion bulb size, most of large sized onions were produced in upland cultivated condition. Average bulb production for seed harvesting were $63{\sim}70%$ higher in paddy cultivated condition than that of upland cultivated condition. The rotted rate of onion was about $27.2{\sim}34.6%$ in paddy, $37.5{\sim}51.4%$ in upland cultivated condition respectively, showed favorable result as the difference of $8.7{\sim}24.2%$ in paddy cultivated condition.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1262-1262
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• 2001

The rice plant is one of the important staple crops in Korea. The high yield with low cost in rice is required the soil fertility and the development of new precise method of fertilizer application by nutritional diagnosis. Now, in Korea, the nitrogen application system for the rice plant is composed of the basal fertilization, fertilization at tillering stage and fertilization at panicle stage, which the nitrogen fertilization at panicle stage amount to about 30 percent in the total amount. Thus, this experiment carried out to the development of the system that can measure the nitrogen content in the rice plant at panicle stage rapidly with the near infrared spectroscopy, and to predict the appropriate quantity of the nitrogen fertilization at panicle stage based on calibration model for test of nitrogen content in rice plant. The samples were collected from 48 varieties in 4 regions which are mainly cultivated in the southern part of Korea. And then, it collected by classifying into the leaf, the whole plant and the stem since 7 days before the nitrogen fertilization at panicle stage. The ranges of the nitrogen contents were 1.6∼4.0%, 1.7∼3.0% and 1.4∼2.7% in the leaf, the whole plant and the stem, respectively. In the calibration models created by each part of the plant under the Multiple Linear Regression(MLR) method, the calibration model for the leaf recorded the relatively high accuracy. The mutual crossing test on unknown samples were carried out using Partial Least Square(PLS) calibration model. That is, the nitrogen content in the stem was tested by calibration model made by the leaf model and that of stem was tested by calibration model made by whole plant sample. When unknown leaf sample was tested by calibration model made by all sample that collected from each part in rice plant such as leaf, stem and whole plant, it recorded the highest accuracy. As a result, to test the nitrogen content in the rice plant at panicle stage, the nitrogen content in the leaf shall be tested by the calibration model composed of the leaf, the stem and the whole plant. In future, to estimated the amount of nitrogen fertilization at panicle stage for rice plant , it will be calculated based on regression model between rice yield and nitrogen content of leaf measured by calibration model made by mixed sample including leaf, stem and whole plant.

• Korean Journal of Remote Sensing
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• v.28 no.1
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• pp.121-128
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• 2012

High resolution intertidal DEM is a basic material for science research like sedimentation/erosion by ocean current, and is invaluable in a monitoring of environmental changes and practical management of coastal wetland. Since the intertidal zone changes rapidly by the inflow of fluvial debris and tide condition, remote sensing is an effective tool for observing large areas in short time. Although radar interferometry is one of the well-known techniques for generating high resolution DEM, conventional repeat-pass interferometry has difficulty on acquiring enough coherence over tidal flat due to the limited exposure time and the rapid changes in surface condition. In order to overcome these constraints, we tested the feasibility of radar interferometry using Cosmo-SkyMed tandem-like one-day data and ERS-ENVISAT cross tandem data with very short revisit period compared to the conventional repeat pass data. Small temporal baseline combined with long perpendicular baseline allowed high coherence over most of the exposed tidal flat surface in both observations. However the interferometric phases acquired from Cosmo-SkyMed data suffer from atmospheric delay and changes in soil moisture contents. The ERS-ENVISAT pair, on the other hand, provides nice phase which agree well with the real topography, because the atmospheric effect in 30-minute gap is almost same to both images so that they are cancelled out in the interferometric process. Thus, the cross interferometry with very small temporal baseline and large perpendicular baseline is one of the most reliable solutions for the intertidal DEM construction which requires very accurate mapping of the elevation.

• Journal of Conservation Science
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• v.33 no.6
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• pp.485-495
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• 2017

The purpose of this study is to evaluate the functionality and lightfastness of the natural pigments according to the type of Seokganju used as Dancheong. The commercially available red iron-oxide-based natural pigments that are called Seokganju and Daija manufactured by traditional methods in Korea and Japan were selected. The analysis of the constituent minerals and constituents of 8 kinds of collected Seokganju showed that most of them contained hematite. There are two types of Seokganju according to the $Fe_2O_3$ contents. The type of Seokganju can be characterized not only using the main component but also from the burn-out processing. The chromaticity results for Seokganju with a high $Fe_2O_3$ concentration indicate dark red or grayish brown, while those for Seokganju with a low $Fe_2O_3$ concentration indicate yellowish red or yellowish brown. Samples were prepared by mixing with a glue solution and functional properties were evaluated based on the opacity and spreadability. Coated samples were used in the lightfastness test. The spreadability and opacity of the pigments were measured differently depending on the main component. Most Seokganju samples a showed slight color change until $9,000kJ/m^2$ but rapid color changes were detected after $18,000kJ/m^2$. In particular, burnt Seokganju showed superior lightfastness.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.189-194
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• 1998

In order to evaluate the residual effects of bituminous coal fly ash, gypsum, oyster shell as soil amendments, Chinese cabbage was cultivated on acidic sandy loam soils with low boron content. The soils were amended in the upper 15cm with amendments in previous year and the growth and qualities of plants were analyzed. Amendments treated one year before were, in metric tons per hectare, i) none(Check) ; ii) 80 fly ash(FA) ; iii) 4 shell(SH) ; iv) 56 fly ash + 24 gypsum (FG) ; v) 40 fly ash + 24 gypsum + 0.8 shell(FGS). Yield response in fresh weight of Chinese cabbage was in order of 834% for FGS > 780% for FG > 755% FA > 193% for SH plants. Reducing sugar, vitamin-C, and total nitrogen contents of leaves depending on treatments showed the same tendencies as that in yields, whereas crude fibre opposite to them. In particular, FA, FG, and FGS plants showed normal growth without both boron deficiency symptoms which appeared in Check and SH plants and possibilities of accumulation of heavy metals. In any soils treated with the above amendments, however, magnesium was insufficient.

• Korean Journal of Environmental Agriculture
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• v.12 no.2
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• pp.176-183
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• 1993

Photolysis experiments were conducted to investigate the stability of a new insecticide, [O,O-Diethyl O-(1-phenyl-3-trifluoromethyl-5-pyrazoyl) thiophosphoric acid ester: KH-502] under the various conditions. In the photolysis experiment, KH-502 was, after being added into the acetone or acetonitrile solution, irradiated under the sunlight or UV lamp $(300{\sim}350nm)$, where acetone or acetonitrile solution was varied with water and $O_2$contents and was treated with humic acid, rosebengal or tryptophan. Results for stability and degradation pattern of KH-502 from the above experiment can be summarized as follows: 1. The significant difference in KH-502 decomposition due to photolysis was shown for between KH-502s irradiated at $300{\sim}350$ nm and non-irradiated. KH-502 was photolyzed in the acetone by the sensitizing effect, but was stable in the acetonitrile. 2. The degradation pattern of KH-502 in the photolysis was different as compared to that in the thermal decomposition, and the decomposed products were O,O-Diethyl O-(1-phenyl-3-trifluoromethyl-5-pyrazoyl)phosphoric acid ester (KH-502 oxo form), O,S-Diethyl O-(1-phenyl-3-trifluoromethyl-5-pyrazoyl)phosphorothiolate(S-ethyl KH-502), 1-Phenyl-3-trifluoromethyl-5-hydroxy pyrazole (PTMHP) and several unknown compounds. 3. Treatments of acetone or acetonitrile solution with humic acid, rosebengal or tryptophan revealed no-sensitizing effect on the photolysis of KH-502. Dissolved oxygen in the acetone played as a cosensitizer with acetone competitively to enhance the photolysis of KH-502. 4. Treatments of acetone with humic acid or paddy soil water collected from fields decreased the photolysis of KH-502.

• Journal of the Korean Society for Marine Environment & Energy
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• v.2 no.1
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• pp.102-112
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• 1999

The purpose of this study is to evaluate the effects of design criteria and environmental conditions of the site of created tidal flats on the structure and function of man-made ecosystem. Seven constructed tidal flats and three natural tidal flats were studied taking the difference in the location (wave height and tidal current), inflow of river water, slope of tidal flat and age after the construction completed into consideration. Parameters studied were physico-chemical and biological characteristics of soils and rate of respiration. The natural tidal flats had higher contents of silt, nitrogen and organic matter compared with the constructed ones. The natural ones had reductive zone below 2cm, whereas the constructed ones had aerobic zone from the surface to below 20cm. The bacterial population in the soil of the constructed tidal flats was one to two orders of magnitude lower than that in the natural ones. Both biomass of macrobenthos and microbial respiration rate, however, were not different significantly between the natural and the constructed tidal flats. There was an exceptional constructed tidal flat with similar physico-chemical and biological characteristics to the natural ones. It is most probable that sufficient conditions to have similar tidal flats to natural ones are the location in enclosed bay or calm coastal area. Thus, to make man-made tidal flats with the same characteristics as those in natural ones, man-made tidal flats should be designed and/or located to enhance the accumulation of silt on tidal flat. It is important to select a place having low water motion for construction of tidal flat.

• Journal of Microbiology and Biotechnology
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• v.25 no.9
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• pp.1467-1475
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• 2015

The use of microbial extracts containing plant hormones is a promising technique to improve crop growth. Little is known about the effect of bacterial cell-free extracts on plant growth promotion. This study, based on phytohormonal analyses, aimed at exploring the potential mechanisms by which Enterococcus faecium LKE12 enhances plant growth in oriental melon. A bacterial strain, LKE12, was isolated from soil, and further identified as E. faecium by 16S rDNA sequencing and phylogenetic analysis. The plant growth-promoting ability of an LKE12 bacterial culture was tested in a gibberellin (GA)-deficient rice dwarf mutant (waito-C) and a normal GA biosynthesis rice cultivar (Hwayongbyeo). E. faecium LKE12 significantly improved the length and biomass of rice shoots in both normal and dwarf cultivars through the secretion of an array of gibberellins (GA₁, GA₃, GA₇, GA₈, GA₉, GA₁₂, GA₁₉, GA₂₀, GA₂₄, and GA₅₃), as well as indole-3-acetic acid (IAA). To the best of our knowledge, this is the first study indicating that E. faecium can produce GAs. Increases in shoot and root lengths, plant fresh weight, and chlorophyll content promoted by E. faecium LKE12 and its cell-free extract inoculated in oriental melon plants revealed a favorable interaction of E. faecium LKE12 with plants. Higher plant growth rates and nutrient contents of magnesium, calcium, sodium, iron, manganese, silicon, zinc, and nitrogen were found in cell-free extract-treated plants than in control plants. The results of the current study suggest that E. faecium LKE12 promotes plant growth by producing GAs and IAA; interestingly, the exogenous application of its cell-free culture extract can be a potential strategy to accelerate plant growth.