• Korean Journal of Soil Science and Fertilizer
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• v.16 no.2
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• pp.119-125
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• 1983

To find out problems and changing soil properties induced by leveling of paddy, a field survey was carried out with questionares to farmers of 68 project areas (990 farmers). The soil characteristics between natural soils and cut out sites was compared with soil samples taken from 37 project areas. More than 70 percents of farmers answered to the questionares expressed satisfaction on the paddy land leveling project; however, some farmers replied dissatisfaction that the arable land was decreased the soil productivity due to loss of surface soil or insufficient surface leveling, that the government support was insufficient and that transplanting of rice might be delayed due to retardation of the project. 1. The rate of cut out soils during the land leveling on plain terrain was about 15.3%, but the rates on gently sloped terrain (2-7% slopes) and sloped terrain (7-15% slopes) were relatively high showing 25.9% and 45%, respectively. 2. The deterioration of physical properties was clear in cut out site where the hardness and bulk density increased and the porosity and the rate of water stable aggregate decreased. 3. The degree of deterioration of physical properties on the Diluvial terrace was more severe than on plains or sloped alluvial fans and valleys. The decrease of available phosphorous and the content of organic matter in the cut out place due to land leveling were prominent. 4. The rice yield from cut site was decreased by 28% comparing with that from natural soils.

• Korean Journal of Weed Science
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• v.32 no.1
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• pp.1-9
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• 2012

This study was conducted to survey vegetation changes and soil characteristics in Saemangeum new reclaimed tidal land. Soil salinity in border area to tidal land was 22.3 dS $m^{-1}$ but showed 1.1~3.44 dS $m^{-1}$ over the distance of 2 km from border line. The vascular plants in survey sites were recorded as total 26 taxa in 6 families. The frequency of species appearance of Aster tripolium, A. subulatus var. sandwicensis were highest by 61.5 and that of Phragmites communis, Puccinellia nipponica were 53.8. The almost vegetations occurred in the patch which range of soil salinity 14 dS $m^{-1}$ were halophytes as Salicornia europaea, Suaeda asparagoides, S. japonica. As lowed soil salinity as 6.7 dS $m^{-1}$, mixed vegetation of halophytes with P. communis, P. nipponica, Carex pumila were occurred. Dominant species in the range of 3.0 dS $m^{-1}$ area were A. subulatus var. sandwicensis, P. communis, Echinochloa spp., Zoysia sinica and Conyza canadensis. Biomass production was the highest in the area of dominant vegetation with P. communis, and mixed zone with P. communis and Aeschynomene indica are followed. The correlation between vegetation biomass and soil salinity, soil pH and dominance index of vegetation were negative. But that of vegetation biomass and soil organic content were positive.

• Journal of the Mineralogical Society of Korea
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• v.15 no.1
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• pp.1-10
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• 2002

The present study is focused on the granite weathering and soil formation, and the heavy metal contamination in soils in the Onsan industrial area. For profile study, soil sampling was conducted on each depth and experimental analyses have been conducted on those samples. X-ray diffraction analyses show that clay minerals consist mainly of kaolin minerals, vermiculite, and minor illite. Most of kaolin minerals in the lower kiwi of the profile consist of halloysite as confirmed by formamide intercalation, but the content of halloysite decreases gradually toward the surface since it has been transformed to kaolinite in the upper part of the profile. Thermal treatment by heating at $110^{\circ}C,\;300^{\circ}C,\;and\;550^{\circ}C$ shows a diffuse and broad peak the between 10 and $14\;{\AA}$ region in X-ray diffractograms. This suggests the possible existence of the hydroxy-Al interlayerecl vermiculite. Na-citrate extraction method reaconfirms this result showing transition of $14\;{\AA}$ peak to $10\;{\AA}$ In by removing the interlayer materials and restoring the vermiculite to its original state. The occurrence of hydroxy-Al interlayered vermiculite is also supported by soil pH distribution room 3.9 In the lower part to 3.6 in the upper part of the profile. Sequential extraction experiment was conducted to investigate the states of heavy metals in soils. The experiment shows that relatively high amounts of heavy metals are concentrated in the upper part of the profile and that most of them are bound to Fe/Mn oxides and organic matters while less concentration in clay minerals. The result indicates that most of heavy metal pollutants are concentrated in the surface soil and that the low concentrations of heavy metals in clays are mainly due to the low adsorption capacities of clay minerals such as kaolin minerals and hydroxy-Al interlayered vermiculite in acidified soil condition.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.2
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• pp.149-157
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• 1988

This study was carried out to prepare the flavoring substance using sardine for instant soup, and to examine the taste compounds and storage stability of the product. In preparation of product, raw sardine are gutted, boiled for 10 minutes and smoked 3 times to $9{\sim}10%$ moisture content at $80^{\circ}C$ for 8 hours. The smoked-dried sardine meat were followed to be 50 mesh of particle size. The powdered-dried sardine were mixed 4.0% sugar, 20.0% table salt, 3.0% monosodium glutamate, 0.2% black pepper, 0.2% garlic powder and 0.2% onion powder, Finally the powdered instant soup product were vacuum packed in a laminated film(PET/A1 foil/CPP) bag, and then stored at room temperature for 120 days. The effect of smoking on enhancing flavor and on preventing lipid oxidation of product during storage were observed. From the chemical analysis and omission test, the principal taste compounds of product were IMP, 478.2mg/l00g; free amino acids such as glutamic acid, histidine, arginine, phenylalaine 3292.5mg/l00g; non-volatile organic acids such as lactic acid, ${\alpha}-ketoglutaric$ acid, 712.2mg/l00g; total creatinine 409.0mg/100g, and small amount of betaine, TMAO. Fatty acid composition of product were mainly consisted of polyenoic acids such as 20:5, 22:6, followed by saturated acids, monoenoic acid. The major fatty acid were 16:0, 16:1, 18:1, 20:5 and 22:6. From the results of sensory evaluation and chemical experiments during storage, the vacuum packed product were good condition for preserving the quality during storage for 120 days. We may conclude that the quality of present product was not inferior to that of seasoning powder of anchovy on the market, and it can be commercialized as a flavoring substance in preparing soup and broth.

• Korean Journal of Environmental Agriculture
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• v.14 no.2
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• pp.135-143
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• 1995

This study was conducted to investigate the adsorption characteristics, distribution coefficients, and movement of alachlor(2-chloro-2', 6'-dimethyl-N-(methoxymethyl) acetanilide) and chlorothalonil(tetrachloroisophthalonitrile) for the 3 soils sampled from major soil groups in Cheju Island. Namwon, Jeju, and Mureng soils used in this study were classified as black volcanic ash soil, dark brown volcanic ash soil and dark brown nonvolcanic soil, respectively. Organic carbon content and CEC of Namwon soil were very high and those of Mureung soil were very low. Linear and Freundlich adsorption isotherms were the best to fit the adsorption of alachlor and chlorothalonil in the soils. K value, Freundlich coefficient, of alachlor for Namwon soil was 21.38, being 5.4 and 97.2 times higher than that for Jeju and Mureung soils respectively. The values of chlorothalonil for the soils were similar to those of alachlor but were much higher than them. When Mureung, Jeju and Namwon soil columns were leached with a solution containing 10.25 mg/l of alachlor and 1.50 mg/l of chlorothalonil, alachlor was first detected at 0.265, 0.47, and 1.86 pore volume (PV) and chlorothalonil was 3.71, 4.7 and 17.5 PV, respectively. The pore volumes at $C/C_o=1$ of alachlor in the leachates from Mureung, Jeju and Namwon soil columns were 1.1, 3.7 and 6.6 PV and those at $C/C_o=0.2$ of chlorothalonil were 7.5, 8.5 and 27.5, respectively. This means that the deceasing order of the mobility of the chemicals in soils was Mureung soil>Jeju soil${\gg}$Namwon soil. The pore volumes detecting $C/C_o=0.5$ of alachlor and $C/C_o=0.05$ of chlorothalonil in leachate were positively correlated with the distribution coefficients for the soils.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.1
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• pp.132-137
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• 2010

This study was performed to investigate the effect of apple and maltitol as ingredients on the quality of Jochung, a grain syrup. Four kinds of Jochung products were prepared from steamed-rice, apple juice, heated-apple sarcocarp (at $70^{\circ}C$, 60 min), and a mixture (sarcocarp : maltitol＝5:1, w/w) by saccharifying (at $55^{\circ}C$, 8 hrs) with a malt (100 g/500 g rice), mixing the ingredients (steamed-rice : ingredient＝5:5, w/w), filtering, and heating the filtrate (at $95^{\circ}C$, 2 hrs): product (A) with apple juice added before saccharified, product (B) with apple juice added after saccharified, product (C) with heated-apple sarcocarp added after saccharified, and product (D) with the mixture added after saccharified. The product (D) had the lowest pH value ($4.60\pm0.01$) of any other products. The contents of reducing sugar and total phenolic compound were the highest in the product (A) among all the products, which comprised $68.10\pm6.71$% and $7.36\pm0.85$ mg/g, respectively, resulting in good quality. The solidity and the dextrose equivalence had the highest value in the product (B) and the product (C), respectively. The malic acid content ($4.10\pm0.02$%) of the product (D) was the highest of any other organic acids identified by HPLC. Hunter L, a, and b values of the product (D) were the highest compared to other products. In sensory evaluation, the product (A) had generally higher score in all sensory attributes. It was concluded from the chemical and sensory evaluation that adding the apple juice before saccharified might be an effective method for manufacturing good quality rice-Jochung.

• Journal of Nutrition and Health
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• v.4 no.4
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• pp.39-46
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• 1971

Since ${\beta}-aminoethylphosphonic$ acid was discovered in the living organism, the biosynthesis and biological function of aminophosphonic acids have been extensively studied. The purpose of this project consists in the two parts: 1)the preparation of DL-1-amino-2-phenylethylphosphonic acid (Phenylalanine aminophosphonic acid) and DL-1-amino-3-methylbutyl-phosphonic acid (Isoleucine aminophosphonic acid) by the method of Chamber and Isbell. 2) the study of metabolism and biological functions of those synthetic materials by the animal experiment (white rats) The importance of this project proved to be the first experience fed by animals for the elucidation of biochemical and metabolic functions in the animal body. The following organic synthesis of DL-1-amino-3-methylbutylphosphonic acid and DL-1-amino-2-phenylethylphosphonic acid are studied. 1)Synthesis of DL-1-amino-3-methylbutylphosphonic acid a) Synthesis of Iso-butylbromide b) Synthesis of Ethyl iso-butylmalonate c) Synthesis of Iso-caproic acid d) Synthesis of $Ethyl-{\alpha}-bromo$ iso-caproate e) Synthesis of $Triethyl-{\alpha}-phosphono$ iso-caproate f) Synthesis of DL-1-amino-3-methylbutylphosphonic acid 2)Synthesis of DL-1-amino-2-phenylethylphosphonic acid a) Synthesis of Diethyl phosphite b) Synthesis of Ethylchloro acetate c) Synthesis of Triethyl phospho acetate d) Synthesis of Triethyl benzyl phospho acetate e) Synthesis of DL-1-amino-2-phenylethylphosphonic acid The synthetic compounds; DL-1-amino-3-methylbutylphosphonic acid and DL-1-amino-2-phenyl ethylphosphonic acid which are essential amino acid (isoleucine, phenylalanine)analogue are supplemented to the animal diet at the level of 0.2% and 0.4% for isoleucine analogue and 0.35% and 0.7% for phenylalanine analogue. The plain isoleucine and phenylalanine at the same level in the diet are fercilitated as comparable groups in this study. Two sets of experience including 100 male rats were carried out for seven weeks each total 14 weeks. During this period, urine samples, and each big organs were collected for the analysis of total nitrogen, phosphorus, and glycogen contents in the individual samples by Micro Kjeldahl Fisk & Subbarow and Nelson Somogye, method. 1) The result of the project a) The yield of DL-1-amino-3-methylbutylphosphonic acid and DL-1-amino-2-phenylethylphosphonic acid showed low tendency at the level of 12.5% and 20% Melting point of those two compounds were very high and the ${\alpha}-amino$ group in the synthetic compounds showed positive reaction with ninhydrin in the violet color. b) Ail the experimental groups included in this study revealed statistically no significant difference in the organ weight, total body nitrogen retention and urinary phosphorus excretion This means isoleucine aminophosphonic acid and Phenylalanine aminophosphonic acid were utilized in the body as much as the plain amino acids, isoleucine and phenylalanine did. c) The glycogen contents in the liver of the phenylalaine aminophosphonic acid gruop showed higher statistically significant(p<0.05) in the comparision with the group of the Phenylalanine and the Standard-2. It was noteworthy that the higher glycogen content in the liver might indicate the significance in the incorporation of phenylalanine aminophosphonic acid into the intermediate of tricarboxylic acid cycle as activated state.

• Korean Journal of Poultry Science
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• v.35 no.3
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• pp.303-311
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• 2008

This study was conducted to investigate the effect of dietary supplementation of Cu-methionine chelate(Cu-Met) and Cu-soy proteinate(Cu-SP) on the performance, small intestinal microflora and immune response in laying hens. A total of 960 Hy-line $Brown^{(R)}$ laying hens of 39 wks old were assigned to one of the following 6 dietary treatment: control(C), antibiotic(Avilamycine 6 ppm), Cu-Met 50 and Cu-Met 100(50 and 100 ppm Cu as Cu-methionine chelate), Cu-SP 50 and Cu-SP 100(50 and 100ppm Cu as Cu-soy proteinate). Each treatment was replicated 4 times with forty birds per replication, housed in 2 birds per cages. Forty birds units were arranged according to randomized block design. Feeding trial lasted 6 wks under 16 hours lighting regimen. Hen-day and hen-house egg production of groups treated with Antibiotic and Cu supplements tended to be higher than the control with significant difference (P<0.05) shown between Cu-Me 100 and control. Egg weight was significantly (P<0.05) heavier in antibiotic and Cu-SP treatments than Cu-Met treatments but they were not significantly different from the control. Eggshell strength, egg shell thickness, egg yolk color and Haugh unit were not significantly different among treatments. There were no significant differences in leukocytes and erythrocytes in the chicken blood. But mean corpuscular hemoglobin value(MCH) was significantly (P<0.05) higher in Cu-SP 100 than antibiotic treatment. The concentrations of serum IgG and IgA were not significantly different among treatments. Copper concentration in the liver tended to increase as the level of copper supplementation increased, that of Cu-SP 100 being significantly (P<0.05) higher than those of the control and antibiotic treatment. Concentrations of iron and zinc of the liver were not significantly influenced by treatments. Populations of Cl. perfringens and Lactobacilli in the small intestinal content were significantly (P<0.05) influenced by treatments. Population of Cl. perfringens decreased and that of Lactobacilli increased in the copper supplemented groups. The result of this experiment showed that Cu-Met and Cu-SP are comparable to antibiotic in improving egg production in laying hens. Birds fed diets supplemented with Cu-SP produced heavier eggs than those fed diets with Cu-Met. There were no significant differences in the performances between 50 ppm and 100 ppm copper supplementation as organic forms.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.3
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• pp.245-254
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• 2000

This study was conducted to investigate the community structure and distributional pattern of meiobenthos in the deep sea bottoms of northeastern Pacific during July 1998. The faunal samples were collected using the multiple corer at ten stations; eight stations along the transects from 5$^{\circ}$N to 12$^{\circ}$N, and two stations in the Preservation Zone and Impact Zone of the KODOS (Korea Deep Ocean Study) area. The organic carbon content in sediments ranged from 0.79 to 1.76 mg cm$^{-3}$, and higher concentration appeared at stations in lower latitudes than 8$^{\circ}$N. The most abundant meiobenthos was nematodes and followed by foraminiferans; these two taxa comprised more than 70% of the total abundance at all stations. The most abundant meiobenthos occurred with mesh size of 0.063 nm. The maximum density of meiobenthos was 442 ind./10 cm$^2$ at station N5, and the density gradually decreased toward station N8 where the minimum density of 92 md./10 cm$^2$ was found. More than 60% of meiobenthos were distributed at surface sediment layer within 1.0 cm, and the peak abundance was found at 0-0.25 cm layer. The latitudinal distribution pattern of meiobenthos in the study area seemed to be related with the primary productivity of the surface water that is also connected to the water circulation pattern of the Pacific Ocean near the Equator, diverging at latitude of 8$^{\circ}$N and conversing at 5$^{\circ}$N.

• Journal of Soil and Groundwater Environment
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• v.10 no.1
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• pp.43-57
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• 2005

Twelve bottom sediments and three cores were collected in Juam reservoir for a study on transportation, which was controlled by particle grain size (2mm-200{\mu}m,\;200-100{\mu}m,\;100-50{\mu}m,\;50-20{\mu}m,\;<20{\mu}m), and vertical distribution of heavy metals. Sediment cores were sliced into 2 to 5 cm intervals to measure heavy metal concentrations in interstitial water and sediments with depth. Pb isotopic compositions of core samples were determined to calculate sedimentation rate. Regardless of sampling sites, levels of heavy metals and trace elements in bottom sediments are nearly constant with mean values of $14.9\;{\mu}g/g\;for\;As,\;0.81{\mu}g/g\;for\;Cd,\;30.7{\mu}g/g\;for\;Cu,\;34.7{\mu}g/g\;for\;Ni,\;63.3{\mu}g/g\;for\;Pb\;and\;87.9{\mu}g/g\;for\;Zn$. In general, Cu, Pb, Zn, Wi, and Cr in fraction of $<20{\mu}m$ exhibit the highest concentration, but content of As is the highest in grain size of $2\;mm-200\;{\mu}m$ and $200-100\;{\mu}m$. Fe and Mn occur as the dissolved compositions of the highest concentrations in interstitial waters and increase in their concentrations toward lower part of cores. On the contrary, concentrations of Zn and Cu show the highest value in the uppermost part in cores, suggesting these elements are released from reductive dissolution of hydroxides and oxidation of organic matters under different redox conditions. The highest accumulations of Cu, Ni, Pb, and Zn contents in the sediment cores are observed at 0-4 cm layers, and concentrations of Cu and Pb are especially high, implying these heavy metals are originated from anthropogenic sources. The apparent sedimentation rate estimated using unsupported $^{210}Pb$ is 0.91 cm $year^{-1}$, corresponding about 10 cm sedimentation in total depth since construction of Juam dam. These results will provide available information for management of bottom sediment in Juam reservoir.