• Journal of Soil and Groundwater Environment
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• v.20 no.5
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• pp.34-40
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• 2015

It is reported that the intensity of rainfall will likely increase, on average, over the world on 2000. For water resources security, many studies for flow paths from rainfall or snowmelt to subsurface have been conducted. In Korea, few isotopic studies for characterizations of flow path have been undertaken. For a better understanding of how water derived from atmosphere moves to subsurface and from subsurface to stream, an analysis of precipitation and stream water using oxygen-18 and deuterium isotopes in a small watershed, Dorim-cheon, Seoul, was conducted with high resolution data. Variations of oxygen-18 in precipitation greater than 10‰ (δ¹⁸O_max = −1.21‰, δ¹⁸O_min = −11.23) were observed. Isotopic compositions of old water (groundwater) assumed as the stream water collected in advance were −8.98‰ and −61.85‰ for oxygen and hydrogen, respectively. Using a two-component mixing model, hydrograph separation of the stream water in Dorim-cheon was conducted based on weighted mean value of δ¹⁸O. As a result, except of instant dominance of rainfall, contribution of old water was dominant during the study period. On average, 71.3% of the old water and 28.7% of rainfall contributed to the stream water. The results show that even in the small watershed, which is covered with thin soil layer in granite mountain region, the stream water is considerably influenced by old water inflow rather than rainfall.

• Journal of the Korean earth science society
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• v.35 no.2
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• pp.97-103
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• 2014

An isotopic hydrograph separation technique has been able to determine the contribution of new water (event water such as rain or snowmelt) and old water (pre-event water like groundwater) to a stream hydrograph for last several decades using stable water isotopes. It is based on the assumption that the isotopic compositions of both new water and old water at a given instant in time are known and the stream water is a mixture of the two waters. In this study, we show that there is a systematic error (standard error in the new water fraction) in the isotopic hydrograph separation if the average isotopic compositions of new water were used ignoring the temporal variations of those of new water. The standard error in the new water fraction is caused by: (1) the isotopic difference between the average value and temporal variations of new water; (2) the new water fraction as runoff contributing to the stream during rainfall or spring melt; and (3) the isotopic differences between new and old water (inversely). The standard error is large, in particular, when new water dominates the stream flow, such as runoff during intense rainfall and in areas of low infiltration during spring melt. To reduce the error in the isotopic hydrograph separation, incorporation of fractionation in the isotopic composition of new water observed at a point should be considered with simultaneous sampling of new water, old water and stream water.

• Journal of Ginseng Research
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• v.4 no.2
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• pp.197-221
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• 1980

Habitat observation, cultural experience of old and present plantation, weather factors in relation to crop stand and water physiology of root and leaf were reviewed. According to habitat observation ginseng plants love water but plate wit talus well grow at drained place with high moisture content in air and soil while ginseng plants were not found in dry or wet place. According to cultivation experience ginseng plants require abundant water in nursery and main field but most old planters believe that ginseng plaints are draught-loving thus require little water. The experience that rain especially in summer i.e unfavorable might be due to mechanical damage of leaves arid leaf disease infection, or severe leaf fall which is caused by high air temperature and coinsided with rain. According to crop stand observation in relation to weather factors abunsant water increased each root weight but decreased total yield indicating tile increase of missing root rate. Rain in summer was unfavorable too. Though rain in June was favorable for high yield general experience that cloudy day and rain were unfavorable might be due to low light intensity under shade. Present leading planters also do loot consider the importance of water in main field. Water content is higher in top than in root and highest in central portion of root and in stem of top. For seedling the heavier the weight of root is tile higher the water content while it reveries from two years old. Water potential of intact root appeared to be -2.89 bar suggesting high sensitivity to water environment. Under water stress water content severly decreased only in leaf. Water content of leaf appeared to be 78% for optimum, below 72% for functional damage and 68% for perm anent wilting. Transpiration or curs Principally through stomata in lower side of leaf thus contribution of upper side transpiration decreased with the increase of intensity. Transpiration is greater in the leaves grown under high light intensity. Thus water content is lower with high light inte nsity under field condition indicating that light is probable cause of water stress in field. Transpiration reached maximum at 10K1ut The decrease of transpiration at higher temperature seems to be due to the decrease of stomata aperture caused by water stress. Severe decrease of photosynthesis under water stress seems to be principally due to functional damage which is not caused by high temperature and Partly due to poor CO2 supply. Water potential of leaf appeared to be -16.8 bar suggesting weakness in draught tolerance. Ginseng leaves absorb water under high humidity. Water free space of leaf disc is %mailer than that of soybean leaf and water uptake appears to be more than two steps.

• Journal of Energy Engineering
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• v.27 no.1
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• pp.40-50
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• 2018

Today, the development of industries and rapid urbanization has a profound impact on the human environment. It can be said that the environment in the craft village is most affected. The environment in these areas is severely degraded and depending on the type of production, the environment in the craft villages is different. In Phong Khe ward of Bac Ninh Province, Vietnam, there are over 204 small and large facilities of recycling and producing paper. The paper facilities produce about 200,000 tons of paper each year and the amount of paper produced is not less than 500 tons each day in Phong Khe. They are creating livelihoods for more than 6,000 workers and generating local budgets from VND- 50 billion to VND 60 billion per year. Despite this great contribution, the use of old machines and "backward" modes of production means that paper recycling has caused serious air, soil, and water pollution in the region. The specific objectives of this study were as follows: (1) provide an overview of paper production process in the Phong Khe paper craft village; (2) comprehensive literature review of the current status of water environment, atmosphere environment, soil environment and solid waste; (3) figure out about waste treatment in Phong Khe ward.

• Journal of Ginseng Research
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• v.35 no.1
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• pp.31-38
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• 2011

In order to distinguish the cultivation area of Panax ginseng, principal component analysis (PCA) using quantitative and qualitative data acquired from HPLC was carried out. A new HPLC method coupled with evaporative light scattering detection (HPLC-ELSD) was developed for the simultaneous quantification of ten major ginsenosides, namely $Rh_1$, $Rg_2$, $Rg_3$, $Rg_1$, Rf, Re, Rd, $Rb_2$, Rc, and $Rb_1$ in the root of P. ginseng C. A. Meyer. Simultaneous separations of these ten ginsenosides were achieved on a carbohydrate analytical column. The mobile phase consisted of acetonitrile-water-isopropanol, and acetonitrile-water-isopropanol using a gradient elution. Distinct differences in qualitative and quantitative characteristics for ginsenosides were found between the ginseng roots produced in two different Korean cultivation areas, Ganghwa and Punggi. The ginsenoside profiles obtained via HPLC analysis were subjected to PCA. PCA score plots using two principal components (PCs) showed good separation for the ginseng roots cultivated in Ganghwa and Punggi. PC1 influenced the separation, capturing 43.6% of the variance, while PC2 affected differentiation, explaining 18.0% of the variance. The highest contribution components were ginsenoside $Rg_3$ for PC1 and ginsenoside Rf for PC2. Particularly, the PCA score plot for the small ginseng roots of six-year old, each of which was light than 147 g fresh weight, showed more distinct discrimination. PC1 influenced the separation between different sample sets, capturing 51.8% of the variance, while PC2 affected differentiation, also explaining 28.0% of the variance. The highest contribution component was ginsenoside Rf for PC1 and ginsenoside $Rg_2$ for PC2. In conclusion, the HPLC-ELSD method using a carbohydrate column allowed for the simultaneous quantification of ten major ginsenosides, and PCA analysis of the ginsenoside peaks shown on the HPLC chromatogram would be a very acceptable strategy for discrimination of the cultivation area of ginseng roots.

• Food Science of Animal Resources
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• v.40 no.3
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• pp.338-349
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• 2020

The effects of organic Zn-L-selenomethionine (Zn-L-SeMet) at 0.3 ppm on carcass composition, meat characteristics, fatty acid composition, glutathione peroxidase activity, and ribonucleotide content were compared against the commercial inorganic sodium selenite (Na-Se) and the combination of the two, in commercial broilers. A total of 540 one day-old chicks were assigned at random to 3 dietary treatments : i) commercial inorganic selenium as control or T1, ii) a 1:1 ratio of inorganic and organic selenium as T2, and iii) organic selenium as T3. Carcass composition, meat characteristics, cholesterol content, fatty acid composition, and ribonucleotide content were generally unaffected by treatments. However, discrepancy were significantly observed in glutathione peroxidase activity (GSH-Px) and water holding capacity, with organic selenium showing higher glutathione peroxidase activity (p<0.01) and lower shrinkage loss (p<0.05), respectively. These findings could be explained by the contribution of organic selenium in bioavailability of GSH-Px. However, having conducted in a commercial close house system with sufficient amount of nutritional supplementation, the present study demonstrated little or no effects of organic Zn-L-SeMet on meat characteristics, fatty acid composition, and ribonucleotide content (flavor characteristic) in broiler chickens.

• Journal of Wetlands Research
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• v.19 no.3
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• pp.279-286
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• 2017

In this study, the characteristics of non-point source pollution runoff and the possibility of using new unit load were investigated by using pollutant load based on monitoring data considering baseflow. For this purpose, the components of hydrograph were separated by using digital filter method and the numerical integration method was applied to calculate the non-point source pollutant load for nine rainfall events in Juwon river in the Geum River basin. As a result of this study, the mean contribution rate of non-point pollutant was 31.34% for BOD, 58.94% for T-N, and 50.42% for T-P and BOD was more influenced by baseflow pollutant. Also, it was analyzed the pollutant load using the new unit load is closer to the observation load than the old unit load. This result implies that it is necessary to manage not only pollutant load due to direct runoff but also pollutant load due to baseflow runoff for efficient water quality management of the watershed.

• Journal of the Korean earth science society
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• v.29 no.6
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• pp.454-465
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• 2008

Benthic foraminiferal assemblage and AMS radiocarbon dating of core sediments from the northern shelf of the East China Sea were analyzed in order to understand the paleoenvironment and sedimentary environmental changes around the Korean marginal seas since the last glacial maximum (LGM). The core sediments, containing continuous records of the last 16,000 years, reveal a series of well-defined vertical changes in number of species (S), P/T ratio and species diversity (H) as well as foraminiferal assemblage. Such down-core variations display a sharp change at a core depth of approximately 240 cm, which corresponds to ca. 10,000 year B.P. The sediments of the lower part of the core (240${\sim}$560 cm, Zone I), including the well-developed tide-influenced sedimentary structures, are characterized by high abundances of Ammonia beccarii and Elphidium clavatum (s.l.) and low values in number of species, P/T ratio and diversity. These tide-influenced signatures and foraminiferal assemblage characters suggest that the sediments of Zone I were deposited in a coastal environment (water depths of 20${\sim}$30 m) such as tidal estuary with an influence of the paleo-rivers (e.g., old-Huanghe and Yangtze rivers) during the early phase of the sea-level rise (ca. 16,000 to 10,000 years) since the LGM. In contrast, the upper core sediments (0${\sim}$240 cm, Zone II) are characterized by abundant Eilohedra nipponica and Bolivina robusta with a minor contribution of A. ketienziensis angulata and B. marginata. and high values in number of species, P/T ratio and diversity. Based on relative abundance of these assemblage, Zone II can be divided into two subzones (IIa and IIb). Zone IIa is interpreted to be deposited under the inner-to-middle shelf environment during the marine transgression in the early Holocene (after ca. 9,000 yr B.P.) when sea level rapidly increased. The sediments of zone IIb most likely deposited after 6,000 yr B.P. under the outer shelf environment (80${\sim}$100 m water depth), which is similar to modem depositional environments. The muddy sediments of zone IIb were probably transported from the old-Huanghe and Yangtze Rivers during the late Holocene. We suggest that the present-day oceanographic conditions over the Yellow and the East China Seas have been established after ca. 7,000${\sim}$6,000 yr B.P. when the Kuroshio Current began to influence this area.

• Korean Journal of Poultry Science
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• v.30 no.4
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• pp.259-267
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• 2003

Two experiments were conducted to investigate the effect of betaine on egg production, lipid metabolism, and osmoregulation in 18-to 42-week-old ISA Brown laying hens. In experiment 1, three hundred and sixty one hens were fed a com-soy basal diet contailing 16% crude protein (CP), 2800 kcal/kg metabolizable energy (ME), 0.33% methionine, and 0, 300, 600, or 1200 mg betaine per kg diet. Egg production, egg weight, feed consumption, feed conversion, and egg quality were measured every eight weeks. Betaine concentration in live and egg were determined along with serum cholesterol, abdominal fat, total serum protein and albumin levels. In experiment 2, twenty thirty-three-week-old laying hens were fed the same diets as those used in experiment 1 in individual cages and the amount of feed and water consumption were measured for two weeks. At the end of experiment 2, all birds were killed to determine blood plasma and ileal osmopressure, arginine vasotocin (AVT), and liver moisture content. In experiment 1, egg production between the treatments during the first eight weeks were not different, whereas the significant increment of egg production were noticed in the birds fed more than 600 ppm betaine after reaching the peak egg production stage (p<0.05). The egg weight was reduced significantly by the betaine supplementation for the first 8 weeks (p<0.05). Feed conversion tended to improve by betaine supplement. Egg quality was not enhanced by betaine supplementation. Liver betaine level increased with betaine feeding compared to the control but betaine concentration in eggs decreased with betaine supplementation. Betaine supplementation elevated the level of serum total cholesterol and triglyeerides compared to the control. Abdominal fat content was increased by betaine supplementation, whereas liver fat content decreased. In experiment 2, water consumption significantly increased in hens fed diets containing 300 and 600 mg betaine/kg (p<0.05) and osmotic pressure of ileal digesta increased with betaine supplement. Liver moisture content was not affected by betaine, but AVT increased in hens fed betaine. The overal results suggested the possibility of using betaine as a feed additives in the laying hens beacuse of its positive contribution to improving egg production and other metabolic parameters related to lipid metabolism.

• Korean Journal of Environmental Biology
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• v.32 no.4
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• pp.297-305
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• 2014

In order to understand the contribution of seaweed aquaculture to nutrients and carbon cycles in coastal environments, we measured the nutrients & carbon uptake rates of Porphyra yezoensis Ueda sampled at Nakdong-River Estuary using a chamber incubation method from November 2011 to April 2012. It was observed that the production rate of dissolved oxygen by P. yezoensis (n=30~40) was about $68.8{\pm}46.0{\mu}mol\;{g_{FW}}^{-1}h^{-1}$ and uptake rate of nitrate, phosphate and dissolved inorganic carbon (DIC) was found to be $2.5{\pm}1.8{\mu}mol\;{g_{FW}}^{-1}h^{-1}$, $0.18{\pm}0.11{\mu}mol\;{g_{FW}}^{-1}h^{-1}$ and $87.1{\pm}57.3{\mu}mol\;{g_{FW}}^{-1}h^{-1}$, respectively. There was a positive linear correlation existed between the production rate of dissolved oxygen and the consumption rates of nitrate, phosphate and DIC, respectively, suggesting that these factors may serve as good indicators of P. yezoensis photosynthesis. Further, there was a negative logarithmic relationship between fresh weight of thallus and uptake rates of nutrients and $CO_2$, which suggested that younger specimens (0.1~0.3 g) were much more efficient at nutrients and $CO_2$ uptake than old specimens. It means that the early culturing stage than harvesting season might have more possibilities to be developed chlorosis by high rates of nitrogen uptake. However, N & C demanding rates of Busan and Jeollabuk-do, calculated by monthly mass production and culturing area, were much higher than those of Jeollanam-do, the highest harvesting area in Korea. Chlorosis events at Jeollabuk-do recently might have developed by the reason that heavily culture in narrow area and insufficient nutrients in maximum yield season (Dec.~Jan.) due mostly to shortage of land discharge and weak water circulation. The annual DIC uptake by P. yezoensis in Nakdong-River Estuary was estimated about $5.6{\times}10^3\;CO_2$ ton, which was about 0.03% of annual carbon dioxide emission of Busan City. Taken together, we suggest more research would be helpful to gain deep insight to evaluate the roles of seaweed aquaculture to the coastal nutrients cycles and global carbon cycle.