• Korean Journal of Soil Science and Fertilizer
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• 제35권1호
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• pp.47-58
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• 2002

Much of the plastic film house soils in the southern part of the Korean peninsula are managed using a upland-paddy rotation culture system (hereafter, RS) to prevent salt accumulation in soil. However, information on the effects of RS on soil properties and environmental conservation is limited. In order to determine the effects of RS on soil properties, 22 fields under RS and 20 fields under a non-rotation system (hereafter, NRS) in plastic film houses were selected in Chinju, in southern Korea, and the P distribution characteristics were investigated, including the chemical properties. The RS contributed to the removal of water-soluble salts in the surface layer and to the redistribution of organic matter evenly in the soil profile. In the AP horizon, available phosphorus levels were $1,611mg\;kg^{-1}$ in RS and $1,789mg\;kg^{-1}$ in NRS, which markedly exceeds the optimum range for plant cultivation. Total P was lower in RS (average $4,593mg\;kg^{-1}$) than in NRS (average $5,440mg\;kg^{-1}$) and this decrease was taken to be an effect of RS. Inorganic P was the predominant form of P in both systems, followed by organic P and residual P. A soil profile showed that total and inorganic P concentrations decreased with depth in both systems. However, organic P increased withdepth in RS, which was in contrast to that noted in NRS. The increase in organic P with depth in RS implied that organically rather than inorganically derived phosphate moved through the soil. The concentrations of water-soluble P, Ca-P and Al-P were higher in NRS than in RS soil profiles, but the Fe-P concentration was higher in RS than in NRS, which might be affected by the anaerobic conditions found in paddy soils. In both systems, the Al-P form of extractable P predominated in the surface layer, followed by Ca-P, Fe-P and water-soluble P. With increasing depth, the composition rate of Ca-P to extractable P decreased to less than 10% in the 60-70cm depth, as Fe-P dominated at this level. The content of water-soluble P, potentially the main source of eutrophication, was higher in NRS than in RS. These results indicated that the RS used in plastic film houses contributed to the removal of water-soluble salts but only slightly decreased the phosphate concentration.

• Korean Journal of Soil Science and Fertilizer
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• 제35권4호
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• pp.232-242
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• 2002

To investigate the effects of arbuscular mycorrhizal (AM) fungus (Glomus intraradices) colonization on drought-stress tolerance, leaf water potential, chlorophyll concentration, P content and carbohydrate composition were examined in perennial ryegrass (Lolium perenne L.) plants exposed to drought-stressed or well-watered conditions. Drought stress significantly decreased leaf water potential, P content and leaf growth. These drought-induced damages were moderated by mycorrhizal colonization. Drought stress decreased the concentration of soluble sugars in shoots. AM plants had a higher foliar soluble sugar than non-AM plants under drought stress condition. Drought stress depressed the accumulation of starch and fructan in shoots, but stimulated in roots. Under drought-stressed condition, starch concentration in roots was higher in non-AM plants than in AM plants. Fructan was the largest pool of carbohydrates, showing the highest initial concentration and the highest net increase for 28 days of treatment. Drought stress slightly decreased fructan concentration in shoots, but remarkably increased in roots. Under drought-stressed condition, fructan concentrations in non-AM and AM shoots at day 28 were 18.7% and 13.3% lower than the corresponding values measured at well-watered plants. However, in the roots, fructan accumulation caused by drought was lessen 13.6% by mycorrhizal colonization. The results obtained suggest that mycorrhizal colonization improves drought tolerance of the host plants by maintaining higher leaf water status and P status, and by retaining more foliar soluble sugars.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• 제19권4호
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• pp.287-301
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• 2014

In order to understand environment condition and phytoplankton community before and after coastal upwelling, the influences of upwelling events on phytoplankton community were studied at 18 stations located the Southern part of East Sea, Korea from May to August 2013. The surface water masses showed low temperature and high salinity due to upwelling events at coastal stations (A1, B1, C1). Correlation between temperature and nutrients (DIP, r=-0.218, p<0.01; DIN, r=-0.306, p<0.01; silicate, r=-0.274, p<0.01) was significantly negative. This result could be explained that nutrients were supplied to surface water by the upwelling of bottom water. Phytoplankton communities were composed of 186 species. Phytoplankton abundance were relatively high in May (C1, $726{\times}10^3cells\;L^{-1}$) and July (A1, $539{\times}10^3cells\;L^{-1}$). Total chlorophyll a and micro-size fraction ($&gt;20{\mu}m$) increased at coastal stations in July and August, while phytoplankton abundance and total chl. a was much low in June. Dominant species in June was Pseudo-nitzschia spp. of which the cell size was $309{\mu}m^3$. Cell size of Pseudo-nitzschia spp. was smaller than dominant species in other period. Therefore, the increase in total chloro-phyll a and the size of phytoplankton was resulted in the sufficient supply of nutrients. In contrast, these tendencies were not observed at outside stations. These results suggested that coastal upwelling was an important influencing factor to determine the species composition and standing stock of phytoplankton community in the coastal waters of the Southern part of East Sea, Korea.

• Journal of The Korean Society of Grassland and Forage Science
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• 제33권4호
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• pp.304-312
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• 2013

This study was conducted to investigate the effect of total neutral detergent fiber (NDF) and forage-derived NDF (fNDF) on nutrient intake and milk production in Holstein dairy cows. Thirty-six Holstein dairy cows at weeks 4 to 20 of lactation were included in this study. The cows were arranged in a randomized complete block design and assigned to one of six diets: 1) 38% NDF with 18% fNDF (HN-HF); 2) 38% NDF with 15% fNDF (HN-MF); 3) 38% with 12% fNDF (HN-LF); 4) 34% NDF with 18% fNDF (LN-HF); 5) 34% NDF with 15% fNDF (LN-MF); and 6) 34% with 12% fNDF (LN-LF). The cows were fed a total mixed ration twice daily (07:00 and 18:00 h) and given ad libitum access to feed and water throughout the experiment. Data on the intake of nutrients (DM, NEl, CP, NDF, fNDF, NFC), milk yield, composition, fat-corrected milk (FCM), fat and protein corrected milk (FPCM), and energy corrected milk (ECM) were analyzed. Lower dietary concentrations of total NDF or fNDF resulted in an increase in DM, NEl, and NFC intake (p<0.01), milk yield (p<0.05) and a lower milk fat concentration (p<0.01). The LN treatment showed no significant differences in milk fat concentration compared to the HN however, further reduction in fNDF decreased milk fat content (p<0.01). The lowest level of milk fat was observed in the LN-LF diet group. Changes in the dietary concentrations of NDF or fNDF did not affect the concentrations of milk protein or SNF (solid not fat), although the yield of milk protein and SNF increased with higher milk yield (p<0.01). The level of fNDF influenced the level of FCM (p=0.07), as well as FPCM and ECM yield (p<0.05). A highly positive correlation between fNDF intake and milk fat concentration was observed in animals with low NDF compared to those offered high NDF. A strong correlation was also observed between milk yield and low NDF intake compared to high NDF intake.

• Food Science of Animal Resources
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• 제30권3호
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• pp.419-426
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• 2010

This study was conducted to investigate the effect of different castration ages on meat quality and sensory properties of Korean native black goats over 410 days. For the experiment, 32 heads of goat (eight heads/4 treatment) were subjected to either a control (5 month non-castration), T1 (7 month castration), T2 (5 month castration) or T3 (3 month castration). The total weight gain for Korean native black goats was highest in the T2 group after feeding for 410 days and the weight gain/day tended to be similar to the total weight gain. The total feeding amounts were lowest (410.82 kg) in T3; however, the feed intake ratio was 16.39 in T2, indicating that it had the best feed efficiency among groups. The cooking loss and drip loss of the Korean native black goats was highest in the control, being 35.53% and 2.08%, respectively (p<0.05), while the total cholesterol of the treatments was higher than that of the control (p<0.05). Moreover, the overall sensory evaluation of the treatment groups was low, indicating that there was more meat flavor when compared to the controls in terms of juiciness, tenderness, flavor, texture, black goat off-flavor and overall evaluation (p<0.05). T2 was found to have the best meat flavor upon sensory evaluation. Additionally, the meat color of the control showed the highest $L^*$ value and Hue value, while T3 showed the highest $a^*$ value (3.61) and T2 showed the highest $b^*$ value and Chroma. The composition of fatty acids was 53.76% oleic acid in T2, while the amounts of Mono-unsaturated fatty acid (MUFA) were highest in T1 and T2 (p<0.05). As a result, the MUFA/SFA ratios of T1 and T2 were higher than those of the control (p<0.05). In conclusion, it is most advantageous to castrate Korean native black goats at the age of 5 months for the best performance and meat quality.

• Journal of Bio-Environment Control
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• 제13권1호
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• pp.51-55
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• 2004

The most commonly used inorganic nutrient compositions such as Murashige & Skoog medium have been optimized for heterotrophic growth. Therefore, they may not be optimal for photomixotrophic and photoautotrophic growth of plantlets. In photomixotrophic micropropagation, emdium sugar level is often lowered, while light and $CO_2$ levels in vessel are raised, and chlorophyllous explants are used to facilitate photosynthetic carbon acquisition. In a factorial experiment effect of addition (+) and omission(_) of organic materials (OM, 0.5 g ${\cdot}$ $m^{-3}$ each of thiamine, nicotinic acid and pyridoxine and 100 ${\cdot}$ $m^{-3}$ myo-inositiol) combined with three sucrose levels (0, 15, and 30 kg ${\cdot}$ $m^{-3}$) was tested on the growth of potato plantlets. Each of nodal cuttings with a leaf was cultured on 0.1${\times}$$10^{-4}m^{-3}$) MS agar ( 8 kg ${\cdot}$ $m^{-3}$) medium (pH 5.80 before autoclave) in glass test tubes (100 mm${\times}$25mm) capped with a sheet of transparent film with a 6 mm diameter gas permeable filter (5.1 air exchanges ${\cdot}$$h^{-1}$). Cultures were maintained in a room for 27 days at $23^{\circ}C$, 50% RH, 350-450${\mu}mol\;{\codt}\;mol^{-1}CO_2$, 16 h ${\cdot}$ $d^{-1}$ photoperiod at 13${\mu}mol\;{\codt}\;m\;{\codt}\;s^{-1}$ PPFD provided by white cool fluorescent lamps. Growth of potato plantlet in the +OM and -OM treatments were similar, while medium pH was 0.2 scale lower in the latter. Dry weight, % dry matter, and stem diameter enhanced, while shoot to root dry weight ratio, leaf area, chlorophyll concentration per gram dry weight, and medium pH decreased with increasing initial sucrose level. Interaction between OM and sucrose levels was observed in shoot length and medium pH. Results indicate that OM can be omitted from the medium without detrimental effect while addition of sucrose was beneficial for the photomixotrophic growth of potato plantlets under raised light and $CO_2$.

• Current Research on Agriculture and Life Sciences
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• 제2권
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• pp.34-41
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• 1984

This study was conducted to investigate yearly changes of weeds occurring in orchard and to evaluate an effect of continuous herbicide application on weed population in apple fields. Digitaria sanguinalis, Cephalonoplos segetum, Calystegia hederacea, Polygonum aviculare, Echinochloa crus-galli, and Portulaca oleracea were observed to be the problem weeds in orchard with yearly similar species for a three-year, showing D. sanguinalis was single dominant species for a three-year experimental period. An increase of Simpson's index from 0.22 in the first year to 0.33 in the 3 rd year was observed in the oxyfluorfen treated plot, indicating that most of the weed species were well controlled, while in the untreated plot, D. sanguinalis was relatively single dominant species showing Simpson's index, 0.56 in the 1st year and decreased to 0.32 in the 3 rd year meaning diversification of weed species, and the same trend was also observed in community dominance. Dissimilarity coefficient, 41.6, observed in the weed populations of 1st year and 2nd year, increased up to 58.8 between 1st year and 3 rd year's weed populations in the oxyfluorfen treated plot, indicating that weed community was greatly affected by oxyfluorfen treatment. Based on 3 year's dry weight oxyfluorfen treatment controlled 95 % of weeds such as $149.3g/m^2$ dry weight in the untreated control plot, with a little yearly changes of dry weight. Composition of perennial and biennial weeds was about 59% in the herbicide treated plots and 30% in the untreated control, showing a relative increase of these weeds in the treated plot. However, total dry weight of these weeds was markedly low, showing less than 5% of the untreated one. An annual, D. sanguinalis composed of 70% of total dry weight in the untreated control.

• Korean Journal of Environment and Ecology
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• 제33권5호
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• pp.506-514
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• 2019

Unlike natural ecosystems, the urban ecosystem proVides an interdependent enVironment in which wild organisms and urban people co-exist. Hornets (genus Vespa) appearing in urban green and parks haVe a positiVe effect on urban ecosystems, but they also cause ecosystem disserVices that cause physical and psychological discomforts to the urban people. Children's parks, for example, are Very popular among children and residents for easy accessibility, and hornets also use them as bases and habitats. HoweVer, there is still a lack of spatial analysis of habitats and appearance characteristics of hornets in children's parks. This study installed hornet traps in 27 children's parks in Cheonan from April to NoVember 2018 in consideration of the life cycle of hornets. We captured a total of fiVe Vespa species (Vespa crabro, V. analis, V. mandarinia, V. ducalis, and V. Velutina) for 32 weeks and analyzed the emergence of hornets in relation to the composition of seasonal characteristics, species characteristics, and enVironmental spatial information. We captured a total of 818 hornets during the study period. They included 290 V. analis (35.4%), 260 V. crabro (31.8%), 100 V. ducalis (12.1%), 87 V. mandaninia (10.6%), and 81 V. Velutina(9.9%). Most of the hornets showed a common feature that queen hornets were largely captured in May through June after they awake from hibernation, and the number of caught hornets decreased sharply beginning in mid-June, which was the cooperatiVe period. HoweVer, V. Velutina showed a seasonal specificity that more than 80% were captured beginning in the third week of October when other hornet species had already entered a decline phase. The analysis of the number of hornets caught in each spot in children's parks showed significant difference among the spots as 363 hornets (44.3%) were captured in top children's parks, and 35 hornets (4%) were captured in bottom children's parks. In particular, the mean NDVI (Normalized difference Vegetation index) of the top six children's parks was 0.79, and that of the bottom six children's parks was 0.38 (t=2.67*, *=p<0.05), indicating a significant difference. The frequency of capturing hornets was high when the ground around the children's parks was grass or bare land. This study is meaningful as a reference study that confirms the ecological characteristics of hornets appearing in green and parks in the city. We expect it to be a foundation for effectiVe urban green area management in the future.

• Journal of Ginseng Research
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• 제29권1호
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• pp.1-18
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• 2005

Ginseng Radix, the root of Panax ginseng C. A. Meyer has been used in Eastern Asia for 2000 years as a tonic and restorative, promoting health and longevity. Two varieties are commercially available: white ginseng(Ginseng Radix Alba) is produced by air-drying the root, while red ginseng(Ginseng Radix Rubra) is produced by steaming the root followed by drying. These two varieties of different processing have somewhat differences by heat processing between them. During the heat processing for preparing red ginseng, it has been found to exhibit inactivation of catabolic enzymes, thereby preventing deterioration of ginseng quality and the increased antioxidant-like substances which inhibit lipid peroxide formation, and also good gastro-intestinal absorption by gelatinization of starch. Moreover, studies of changes in ginsenosides composition due to different processing of ginseng roots have been undertaken. The results obtained showed that red ginseng differ from white ginseng due to the lack of acidic malonyl-ginsenosides. The heating procedure in red ginseng was proved to degrade the thermally unstable malonyl-ginsenoside into corresponding netural ginsenosides. Also the steaming process of red ginseng causes degradation or transformation of neutral ginsenosides. Ginsenosides $Rh_2,\;Rh_4,\;Rs_3,\;Rs_4\;and\;Rg_5$, found only in red ginseng, have been known to be hydrolyzed products derived from original saponin by heat processing, responsible for inhibitory effects on the growth of cancer cells through the induction of apoptosis. 20(S)-ginsenoside $Rg_3$ was also formed in red ginseng and was shown to exhibit vasorelaxation properties, antimetastatic activities, and anti-platelet aggregation activity. Recently, steamed red ginseng at high temperature was shown to provide enhance the yield of ginsenosides $Rg_3\;and\;Rg_5$ characteristic of red ginseng Additionally, one of non-saponin constituents, panaxytriol, was found to be structually transformed from polyacetylenic alcohol(panaxydol) showing cytotoxicity during the preparation of red ginseng and also maltol, antioxidant maillard product, from maltose and arginyl-fructosyl-glucose, amino acid derivative, from arginine and maltose. In regard to the in vitro and in vivo comparative biological activities, red ginseng was reported to show more potent activities on the antioxidant effect, anticarcinogenic effect and ameliorative effect on blood circulation than those of white ginseng. In oriental medicine, the ability of red ginseng to supplement the vacancy(허) was known to be relatively stronger than that of white ginseng, but very few are known on its comparative clinical studies. Further investigation on the preclinical and clinical experiments are needed to show the differences of indications and efficacies between red and white ginsengs on the basis of oriental medicines.

• Korean Journal of Heritage: History & Science
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• 제54권4호
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• pp.232-245
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• 2021

The present study is about a brand development strategy that utilizes Korean traditional patterns. The global culturenomics phenomenon confirms the value of the cultural aspects of design when a national brand is established. People succeed with their unique aesthetic sense and reinterpret it in a modern view, and this design acts as today's national brands. In this way, people used traditional patterns and original designs, along with regional characteristics and formative style, in developing their designs. However, due to recent changes in the global environment, modern people live in an "untact" world, and consumption culture shifted toward online marketing. In this environment, where one is isolated from social activities, there needs to be a strong image that can dramatically change the mood of one's home. I would like to re-examine the Dan-Chung pattern, whose painting depends on the aesthetic characteristics of architecture to protect the wooden members of the framework in traditional architecture. The pattern and color of Dan-Chung, coated in traditional architecture, differs by the type of construction used, which includes a palace, a Buddhist temple, and a Confucianism Dan Chung. The Geummoon pattern contains aesthetic factors to add solemnity to the Main Buddhist Halls, which contain Buddha. This is a new medium that continues the current traditions instead of remaining in the past. Among different Dan Chung patterns, Geummoon has magnificent decoration consisting of the highest grade materials and unique composition; therefore, it is suitable to be reinterpreted in modern terms. The same pattern can be interpreted in different ways with different colors, so there is a great aesthetic impression in the Geummoon pattern. The value of preservation for exploration and theoretical study of the traditional pattern is important, but recreating the pattern into modern formative art can present a new angle of view and national brand, bearing pride in our cultural assets. The study used multidimensional molding methods for realistic presentation after going through the two-dimensional design process. The significant value of Korean molding beauty which hangs onto the past will play a crucial role in establishing our national brand.