• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.20 no.2
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• pp.78-91
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• 2015

Macrobenthic community was studied at 87 stations including intertidal and subtidal area in Yoja Bay, south coast of Korea in summer season of July 2001. Duplicate sediment samples were taken using a van Veen grab ($0.1m^2$) in each station. Mud facies of the sediments were widly distributed in the bay. And relatively high content of sand was shown in the Bulgyo-cheon stream estuary. A total of 274 species was occurred with a mean density of $2,346ind./m^2$ and a mean biomass of $78.2g/m^2$. The polychaetes were species- and density-dominant faunal group with a total of 122 species (44.5% of the total number of species), and mean density of $1,543ind./m^2$ (65.8% of the mean density). Meanwhile, molluscs were biomass-dominant faunal group with $44.4g/m^2$. Bio-Env. analysis showed that the combination of bottom salinity and sand content of the surface sediments was highly correlated to the major macrobenthic communities. The macrobenthic species number, decreasing toward inner bay from mouth of the bay, was significantly correlated to the sediment environmental variables and bottom water salinity. The spatial distribution of abundance showed significant correlation to the sand and mud contents and mean grain size of the surface sediments. Major dominant species were Minuspio japonica (polychaete) with a mean density of $1,167ind./m^2$ at upper part of the bay where salinity was low and Eriopisella sechellensis (amphipod) with $152ind./m^2$ in central part of the bay. Species diversity (H') was $3.0{\leq}$ in the mouth part of the bay and ranged 2.0-3.0 in the inner part of the bay, which showed a significant positive correlation to bottom salinity. Total number of species also showed significant correlations to the sediment composition and bottom salinity. Based on the cluster analysis the macrobenthic community of the bay was classified into five station groups from the bay mouth toward the inner part of the bay depending on the species composition. From the SIMPER analysis Minuspio japonica, Eriopisella sechellensis and Sternaspis scutata mainly contributed to the classification of station group. These results suggested that the macrobenthic communities of the bay were mainly influenced by bottom salinity together with sediment composition, and that the studies of spatial distributions of major dominant species and benthic communities should be conducted continuously to monitor the Yeoja Bay benthic environment.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.624-630
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• 2010

In order to investigate the effects of continual pre-plant application of liquid pig manure (LPM) on growth and quality of rice in double cropping system of rice and malting barley, the liquid pig manure was applied after harvesting rice and malting barley for 3 years. Field experiment was designed with non-fertilizer, chemical fertilizer (CF) 100% recommended by soil testing, rice (LPM 50%+CF 50%)+malting barley (CF 100%), rice (LPM 50%+CF 50%)+malting barley (LPM 50%+CF 50%), rice (LPM 100%)+malting barley (CF 100%) and rice (LPM 100%)+malting barley (LPM 100%). The yield of rice was increased by 13% with increasing culm length and No. of panicle per hill as 482 kg $10a^{-1}$ in rice (LPM 100%)+malting barley (LPM 100%) plot compare with 427 kg $10a^{-1}$ in rice (CF 100%)+malting barley (CF 100%) plot. Whereas, lodging index was high in rice (LPM 100%)+malting barley (LPM 100%) plot by increasing of internodes length from 3rd to 4th and decreasing of breaking strength. When the quality of milled rice was compare with rice (CF 100%)+malting barley (CF 100%) plot, it was decreased by increasing of protein contents and decreasing of rate of perfect grain in rice (LPM 100%)+malting barley (LPM 100%) plot. The content of amylose was not significant by 19.4~22.0%. Toyo-taste value was not different in LPM 100% and CF 100% plot. Rice could be grown with only liquid pig manure 100%, but considering yield and quality of rice and lodging risk, basal fertilization by LPM 50% and top-dressing by CF 50% application was recommended for rice cultivation.

• Journal of the Mineralogical Society of Korea
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• v.16 no.3
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• pp.201-213
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• 2003

The adsorption property and ability of domestic zeolites for some heavy metal ions (Ag, Pb, Cr, Cu, Zn, Mn), which may cause a serious environmental problem in industrial wastewater, were evaluated on ore unit through a series of adsorption experiments together with careful examinations of mineral composition and properties of the zeolites. Though the adsorption behavior basically took place in the form of a cation exchange reaction, the higher CEC value does not necessarily to imply the higher adsorption capacity for a specific heavy metal. A general trend of the adsorption selectivity for heavy metals in the zeolites is determined to be as follow: $Ag\geq$Pb>Cr,Cu$\geq$Zn>Mn, but the adsorption properties of heavy metal ions somewhat depend on the species and composition of zeolite. Clinoptilolite tends to adsorb selectively Cu in case of Cr and Cu, whereas heulandite prefers Cr to Cu. A dominant adsorption selectivity of the zeolite ores for Ag and Pb is generally conspicuous regardless of their zeolite species and composition. The zeolite ores exhibit a preferential adsorption especially for $Ag^{+}$ so as not to regenerate when treated with $Na^{+}$ . In the adsorption capacity for heavy meta ions, the zeolites differ in great depending on their species: ferrierite>clinoptilolite>heulandite. Considering the CEC value of mordenite, the mordenite-rich ore appears to be similar to the clinoptilolite ore in the adsorption capacity. The adsorption capacity for heavy metals is not positively proportional to the CEC values of the zeolites measured by the exchange reaction with ammonium ion. In addition, the adsorption capacity roughly tends to depend on the zeolite contents, i.e., the grade of zeolite ore, but the trend is not consistent at all in some ores. These may be caused by the adsorption selectivity for some specific heavy metals, the presence of possible stacking micro-faults and natural cations such as K hardly to exchange in the zeolite. Considering the economic availability and functional effectiveness as natural zeolite resources, clinoptilolite ores could be applicable to utilize the domestic zeolites for the removal of heavy metals.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.7
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• pp.1212-1217
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• 2004

The aim of this study was to investigate Quality characteristics of Pleurospermum kamtschaticum to increase the value of functional food resources. To examine Quality characteristics of Pleurospermum kamtschaticum, various factors such as color, texture, fiber, minerals, tannin, crude proteins, crude lipids and sensory quality, were determined using physicochemical methods. The contents of dietary fiber were 0.57％ and 0.54％ in each 100 g of leaf and stem parts (freeze drying base). In mineral content, potassium was the highest value in both of leaf and stem parts (freeze drying base). The contents of tannin were 108.1 $\mu$g/mL and 20.9 $\mu$g/mL in leaf and stem parts (fresh base) respectively. Blanching stems showed significant difference in hardness from freeze-drying leaves. The antioxidative activity in ethanol extracts of Pleurospermum kamtschaticum was investigated using peroxide value and free radical scavenging activity. Free radical scavenging activity in ethanol extracts of Pleurospermum kamtschaticum was 43.5％ in a 100 $\mu$g/mL level, and the antioxidative index was 1.09 in a 500 $\mu$g/mL level. For functional food using Pleurospermum kamtschaticum the contents of crude proteins and lipids were about 9％ and 26％, respectively. The results from sensory evaluation of each treatment older age showed a better acceptability.

• Korean Journal of Poultry Science
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• v.31 no.4
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• pp.229-235
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• 2004

A study was conducted to examine the effect of dietary supplementation of multiple probiotics (EM) on growth performance, blood cholesterol, intestinal micro flora, and fecal gas emission in broiler chicks. A total of 450 one day old male broiler chicks (Ross $\times$ Ross) were divided into six treatments with five replications in each treatment for five weeks. Treatments were factorially designed with two levels of diet containing probiotics (DW; 0, $0.2\%$) and three levels of drinking water containing probiotics (DW; 0, 0.01, $0.1\%$). Basal diets contained $21.5\%$ CP and 3,100 kcal/kg ME for starting and $19\%$ CP and 3,100 kcal/kg ME for finishing period. Weight gain, feed intake, and feed conversions of birds fed with probiotics were not significantly different between Ds. Total cholesterol and triglyceride levels were significantly lower (P<0.05) in birds fed with DW $0.01\%$ or $0.1\%$ compared with no probiotics group, but there was no significant difference between D treatments. The number of E. coli, Salmonella and Lactobacillus in the ileum and cecum of the birds fed multiple probiotics were not significantly different from those of no probiotic groups. There were no significant differences in the $CO_2$ gas emissions of fecal between birds fed with Ds or among birds fed with DW. However, $NH_3$ gas emissions of DW $0.1\%$ were significantly lower (P<0.05) than DW $0\%$. In the results of this study, supplementation of probiotics tended to decrease the serum cholesterol and triglyceride compared to those of control groups and reduction of fecal $NH_3$ gas emission.

• Journal of Wetlands Research
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• v.11 no.3
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• pp.49-59
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• 2009

Seasonal changes of the growth characteristics and biomass of Scirpus fluviatilis, a aquatic emergent vascular plant, were investigated to reveal the phenology and the population dynamics and to provide the fundamental resources for the restoration counterplan of the wetland vegetation in the littoral zone of the Upo wetland, Changnyeong-gun, Gyeongsangnam-do, Korea from March 2006 to November 2006. Scirpus fluviatilis was distributed commonly in Upo, Mokpo, Sajipo, Jokjibyeol, and Topyeongcheon upstream and downstream of Upo wetland, and the density was highest in Mokpo. Distribution range for the water depth was 9~49cm, and the highest shoot density in 26~49cm, and the mean shoot density was $119/m^2$, and the mean shoot length was 122.3cm on May 28. The number of the tuber was $104.5/0.25m^2$, and the living tubers were 84.2%. The mean fresh biomass of the living tubers was 3.0g, and those of 1~4g was most as 57.9%. Germination rates of the living tubers was 43.8%, and the maximum rate was in 7~9g and more than 10g. In the pot cultivation, the shoot density of the germinated tubers and the dormant tubers were highest as 13.5 and 9.7, respectively in early August. In the field study, the shoot density had few change before typhoon damage, while the density increased abruptly in November after flooding accompanied with the typhoon 'Ewiniar'. The shoot length in the pot cultivation and in the field study were 100~116cm and 60~170cm, respectively in the growth-end. Biomass allocation rates into the stem, leaf, flower, and underground parts were 8.9%, 6.6%, 0%, and 84.5%, respectively in the pot cultivation of the germinated tubers, and those of the dormant tubers were 7.1%, 7.1%, 0%, and 85.8%, respectively. The tuber number increased to 1.4~4.1 times by the growth-end, so it is concluded that Scirpus fluviatilis is mostly propagated by the vegetative reproduction.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.2
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• pp.131-146
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• 2014

High-resolution seismic profiles coupled with sediment sampling were analyzed to investigate the acoustic characters and distribution patterns of the late Holocene sediments in Gamak Bay of the South Sea, Korea. The mean grain size of surficial sediment lies around $6.3{\sim}9.7{\Phi}$. Sediments in the bay consist of silt and clay with progressive decrease toward the inner bay. The seismic sedimentary sequence overlying the acoustic basement can be divided into two sedimentary units (GB I and II) by a prominent mid-reflector (Maximum Flooding Surface; MFS). The acoustic basement occurs at the depth between 20 m and 40 m below the sea-level and deepens gradually southward. The GB I, mostly occupying the channel-fill, is characterized by reflection-free seismic facies. It can be formed as late Transgressive System Tract (TST), interpreted tidal environment deposits. MFS appears at the depth of about 15~28 m below the sea-level and is well defined by even and continuous reflectors on the seismic profile. The GB II overlying MFS is composed of acoustically transparent to semitransparent and parallel internal reflectors. GB II is interpreted as the Highstand System Tract (HST) probably deposited during the last 6,000 yrs when the sea level was close to the present level. Especially, it is though that the GB II was subdivided into two layers (GB II-a and II-b) by a HST-reflector and this was classified by wind, sea water flux, and tidal current.

• Journal of Animal Science and Technology
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• v.45 no.4
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• pp.649-658
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• 2003

Early introducing the ducks into the paddy field involves a variety of environmental changes such as new surroundings and contact with water, so that some free-ranged ducks show behavioral and physiological changes indicative of stress or die from not adapted for new circumstances. Moreover, the free-ranged ducks was tread on the rice plant, and required a great deal of labor and time for captured the ducks after finishing the introducing. The aim of the present study was to examine the effect of accustoming and imprinting of duckling on behavior patterns, body weight gain and yield of the rice plant in paddy fields. Three paddy plots were used as control (no imprinting and no contact with people), taming (imprinting and regular handling) and roughness (handling roughly and strike terror to ducks) plots. Right after introducing the ducks into the paddy field, eating and moving behaviour of taming plot ducks tended to be longer time spend than that of other treatments. However, eating and moving time tended to be longer in the control than that of other two treatments on the 2 weeks after. Flighting distance was not showed in the free-ranging period taming plot, but the control plot was significantly (P<0.05) longer than the roughness plot. The captured time of free-ranged ducks tended to be shorter in the order of taming, control and roughness plots. Body weight gains was not significant. The number of rice plants damaged by free-ranging ducks in the taming plot were significantly (P<0.05) less than that in the control plot, but the yield and yield components of the rice plant were not differ among 3 treatments. These results indicated that the imprinting or regular handling and related treatments of duckling was reducing badly damage of rice plants, captured time and labor of free-ranged ducks in paddy field, although the working behavior of ducks and yield ability of the rice plants were not affected.

• Korean Journal of Environmental Agriculture
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• v.12 no.2
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• pp.153-161
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• 1993

This study was conducted to compare the resistance and sensitivity of trees with 6 native species exposing to 4 different levels of $SO_2$gas(0.4, 0.7, 1.5 and 3.0 ppm) respectively. The results are summarized as follows : 1. Visible injuries appeared as spots in the region of intervein on the leaves for all the species and the color of the spots changed from light green and/or brown to light brown, dark brown, and/or redish brown. 2. The sensitivity of the species to $SO_2$ was high in the descending order of Zizyphus jujuba, Cataegus pinnatifida, Viburnum sargentii, Weigela subsessilis, Euonymus japonica, and Acer ginnala. 3. The resistance of the species to $SO_2$ was high in the descending order of Acer ginnala, Eunymus japonica Viburnum sargentii, Weigela subsessilis, Zizyphus jujuba, and Crataegus pinnatifida. 4. When the trees were exposed to $SO_2$gas, the contents of chlorophyll a, b, and a+b were consostently lower than those of control, and water soluble sulfur contents in the leaves were higher than those of control. 5. There was no significant correlation between stomatal resistance and the sensitivity(or resistance) of the trees exposed to $SO_2$ gas. 6. In this study, it was concluded that Acer ginnala was more suitable species than the others for landscape in air polluted area because it showed high resistance, low sensitivity, and low stromal resistance to $SO_2$gas exposure.

• The Journal of Engineering Geology
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• v.26 no.4
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• pp.531-549
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• 2016

The purpose of this study is to analyze the relationship of hydrochemistry, geology, fault with occurrence of uranium and radon-222 from the groundwater in the Yeongdong area. In this study, 49 groundwater and 4 surface water samples collected in the study area were collected on two separate occasions. The surface radioactivities were measured at 40 points to know the relationship between the occurrence of uranium in groundwater and surface geology. The chemical composition of groundwater showed three types : $Ca-HCO_3$, $Na-HCO_3$ and $Ca-HCO_3(SO_4,\;NO_3)$. Two groundwater of 49 samples exceeded the maximum contaminant levels of uranium, $30{\mu}g/L$, proposed by the Ministry of Environment of Korea and 11 groundwater of 40 samples for Rn-222 concentrations exceeded the 148 Bq/L maximum contaminant level of US EPA. Most of unsuitable groundwater are located in the geological boundary related with the biotite gneiss and the surface radioactivities of rock samples showed no relationship with groundwater geochemical constituents. The strike-slip fault, Youngdong fault, is $N45^{\circ}E$ direction and the high concentrations of uranium in upper part of fault, consisted of granite and granitic gneiss are detected but in lower part, consisted of metamorphic sedimentary rock are not detected. It suggests that the natural radioactive concentrations are related with the geologic characteristics and the migration and diffusion of natural radioactive materials are affected by the fault.