• Journal of Life Science
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• v.17 no.8 s.88
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• pp.1104-1110
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• 2007

The number of investigated fish collected from the Andong and the Imha reservoir were 2,540 individuals 20 species belonging to 7 families, 850 individuals 11 species belonging to 4 families respectively from May 2005 to March 2006. The total number of the common 3 species individuals investigated caught from the Andong reservoir and the Imha reservoir were 486 individuals and 124 individuals respectively. The investigated individuals is similar(${\pm}2.5$ mm) to 171 individuals make a comparative study. The Opsariichthys uncirostris, Culter brevicauda, Hemiculter eigenmanni of length-weight relationship were TW = $0.00007TL^{3.0543}$, TW = $0.0000009TL^{3.3654}$, TW = $0.00000^{3.3872}$ in the Andong reservoir and TW = $0.00002TL^{2.8493}$, TW = $0.00001TL^{2.8744}$, TW = $0.000004TL^{3.1082}$ in the Imha reservoir respectively. The Condition factor(K) of the Andong reservoir showed the positive slopes in all three species and to be in a good nutrition condition; where as the condition factor(K) of the Imha reservoir showed the negative slopes in two species except in H. eigenmanni and appeared to be in a little bad nutrition condition. Relative condition factor(Kn) indicating that O. uncirostris and C. brevicauda in Andong reservoir is more rotund than ones of Imha reservoir but H. eigenmanni in the Imha reservoir is more rotund than the ones of the Andong reservoir.

• Korean Journal of Plant Taxonomy
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• v.44 no.4
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• pp.281-287
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• 2014

The present study was conducted to understand the growth pattern, pollinators and their frequency of visits of Euphorbia helioscopia population which is located at Tongyoung areas in Korea. The vegetative parts of the species grow early in March, and flowering begins in the middle of the month, and pollination was completed at the mid of April. As a typical form of early spring type, the fruits of E. helioscopia were matured between early in April and May, and the upper parts of plants were disappeared between May and June. During the blooming season about 11 insects species which belong to Diptera, Hymenoptera, Coleoptera and Heteroptera were the most common groups found on this plants. Among them the species of Diptera are the most dominant pollinators for E. helioscopia which is concordant to previous reports in Euphorbia species. Despite of significant numbers of insect visitors in Euphorbia species being reported, E. helioscopia attracts only 11 insect species in study areas, and the paucity of species probably associates with the insect fauna in Tongyoung areas or typical patterns of early spring bloomer of Euphorbias. We observed majority of Diptera species to visit in the morning, and the frequency of visit decreased in the afternoon. Thus, it suggests that the visiting activity of Diptera species is not associated with the temperature increase which was reported in Euphorbia species. However, the number of the cyathium during the blooming season is likely to be related to the frequency of visit of pollinators in E. helioscopia.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.2
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• pp.80-88
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• 2013

The present study was conducted to evaluate relationship between nonylphenol uptake rate and clearance rate of Ruditapes philippinarum, Corbicula japonica and Mytilus edulis. Variation of the temperature and body size of the bivalves was used to modulate clearance rate and nonylphenol uptake rate in this experiment. Clearance rate and nonylphenol uptake rate experiments were determined for two different size classes of the bivalves (R. philippinarum: 0.35, 0.73 g, C. japonica : 0.047, 0.1000g, M. edulis: 0.30, 0.37 g; mean flesh dry weight) and three different temperature regime (5, 13 and $18^{\circ}C$). Weight-specific clearance rate in all animal size and temperature ranges increased in the order of R. philippinarum, C. japonica and M. edulis. The weight-specific nonylphenol uptake rate did not show specific trend among species. The clearance rate and nonylphenol uptake rate generally decreased with animal size and increased with water temperature. For all three species nonylphenol uptake rate had a strong relationship with clearance rate. For a given clearance rate ranges, the nonylphenol uptake rate was in the order of R. philippinarum > C. japonica > M. edulis. The results suggest that water ventilation capacity of filter-feeding organisms is an important physiological factor controlling uptake rate of dissolved nonylphenol.

• Journal of Korean Society of Forest Science
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• v.83 no.2
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• pp.262-269
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• 1994

In order to determine ecological niches of forests in Mt. ManDeok, the studies were analyzed on the methods of TWINSPAN and DCCA ordination. The results are summarized as follows ; Four groups were determined by TWINSPAN : Styrax japonica. Quercus variabilis-Quercus mongolica, Carpinus laxiflora and Fraxinus mandshurica-Cornus controversa communities. In the relations of community structures and environmental factors, Styrax japonica community were distributed in the rich site of magnesium and organic matter, Quercus variabilis-Quercus mongolica community in the low potassium, Carpinus laxiflora community in the low available phosphorus, and the factors in influencing community distribution were elevation. The importance value of Quercus variabilis recorded the highest in all the quadrats sampled and the next values then came those Cornus controversa. Quercus variabilis, Lindera erythrocarpa. Quercus mongolica, Fraxinus mandshurica. Cornus controversa, Symplocos chinensis for pilosa, Acer mono, Carpinus laxiflora, and Styrax japonica in the orders. The species diversities of major dominant species recorded the highest value in the communities of Quercus variabilis-Quercus mongolica but they lowest value in the communities of Fraxinus mandshurica-Cornus controversa.

• The Korean Journal of Pesticide Science
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• v.13 no.2
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• pp.105-110
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• 2009

In 2008, a number of 110 isolates of Colletotrichum gloeosporioides were obtained from infected twigs of persimmon (Diospyros kaki) collected at Sangju and four fungicides (carbendazim, thiophanate-methyl, mancozeb, and propineb) were evaluated to determine their growth effect on fungicide-medium. Among them, the mycelial growth of 68.2 and 35.5% of isolates was inhibited over 91% in response to carbendazim ($415{\mu}g/m{\ell}$) and thiophanate-methyl ($750{\mu}g/m{\ell}$), respectively, compared to untreated control and the correlation between the two benzimidazole fungicides was higher ($r^2=0.7886$). Moreover, in responses to mancozeb ($1,500{\mu}g/m{\ell}$) and propineb ($1,500{\mu}g/m{\ell}$), the inhibition of mycelial growth of 90% and 53.6% of isolates was inhibited over 91%, respectively. But correlation between theses two fungicides was lower ($r^2=0.0174$). There is no cross-resistance response between benzimidazole funficides and mancozeb / propineb.

• Korean Journal of Ecology and Environment
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• v.50 no.3
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• pp.275-285
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• 2017

To investigate the changes of dominant species of benthic macroinvertebrates according to the changes of temperature and precipitation, we surveyed twenty sites of the main Seomjin River in May and September in 2013 and 2014. The temperature, precipitation, water quality factors and substrate composition, which are important factors in benthos habitat environment, were collected and measured. The average temperature of the Seomjin River increased by $0.2^{\circ}C$ in 2014 compared to 2013, and the temperature increased from upstream to downstream, showing a difference of more than $3^{\circ}C$. Also, the annual cumulative precipitation (ACP) was increased toward low latitude. The temperature of Seomjin River increased more than twice in September ($21.7{\sim}24.5^{\circ}C$) after rainfall compared to May ($7.6{\sim}11.3^{\circ}C$) before rainfall, and CP (cumulative precipitation) increased about 3 times before rainfall (263 mm~287.5 mm) and after rainfall (756.3 mm~882 mm). Due to washing effect by summer precipitation, total number of species and individuals for benthic macroinvertebrates were higher in May than in September. Chironomidae sp. and Choroterpes altioculus were dominated in May, Ecdyonurus levis, Macrostemum radiatum and Choroterpes altioculus were dominated in September. As a result of correlation analysis between community indices and environment factors, it was found that there is a high correlation with boulder and sand among substrate compositions. According to the results of cluster analysis based on temperature, CP and the dominant species of benthic macroinvertebrates in Seomjin River, it was divided into two groups following temperature and CP, and the dominant species and geographical position were reflected and divided into detailed groups.

• Journal of Animal Science and Technology
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• v.53 no.4
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• pp.289-296
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• 2011

Swine industry in Korea plays an important role in providing the meat for domestic consumption, and the number of pigs in Korea was about 9.72 million heads as of June, 2010. Meat quality is used to describe any traits which impact the consumer acceptability of fresh meat products. Meat color, firmness, water holding capacity, ultimate muscle $pH_{24h}$ (measured 24 hours post-mortem), shear force, and intramuscular fat percentage (IMF) are generally accepted as important indicators of meat quality and ultimately, consumer acceptance of fresh pork. The objective of this study was to estimate genetic parameters for meat quality traits in Berkshire pigs. The heritability estimates for muscle $pH_{24h}$, lightness (CIE $L^*$), NPPC marbling were 0.61, 0.56 and 0.57, respectively, The heritability estimates for drip loss, cooking loss, shear force were 0.51, 0.66 and 0.56, respectively. The phenotypic correlations between $pH_{24h}$ and lightness (CIE $L^*$), drip loss, cooking loss were negative, ranging from -.45 ~ -.13. The genetic correlations between muscle $pH_{24h}$ and lightness (CIE $L^*$), drip loss were negative, ranging from -.35 ~ -.32. Genetic parameters obtained herein indicate that genetic improvement of muscle $pH_{24h}$ is not related to the NPPC marbling of meat, but rather to improved lightness(CIE $L^*$) and drip loss. Genetic trends of meat quality traits showed increased muscle $pH_{24h}$ and decreased cooking loss and drip loss.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.340-346
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• 2003

The diet food used in this test was composed of the total 16 kinds, such as refined water, herb extract, pomegranate extract, polydextrose and isomalto-oligosaccharide etc. Edible fiber as a major component in dietary food was contained to 2.60%(w/w) level. But the calorie was 104.57kca1/100g, contrast of control domestic saengshick product was 368.06kca1. As a result, calorie of dietary food sample was very low level. Vitamin and mineral as a minor component were determined 5, 6 kinds, respectively. On the other hand, dietary effect of body weight loss was determined about 14%(w/w) at animal test result used for rats during 4 weeks. The reason of dietary effect could confirmed from change of plasma neutral lipids, total cholesterol and HDL-cholesterol concentration. Increasing ratio of these in the general diet and dietary diet feeding groups during 4 weeks were 10.55, 6.90, 9.82% and 6.11, 3.85, 6.11%, respectively. from these results, decrease reason of body weight could confirmed the relative relationship with plasma lipids and cholesterol concentration. But plasma plasma glucose and insulin concentration have not positive relativity.

• Food Science and Preservation
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• v.15 no.3
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• pp.445-449
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• 2008

The total phenolic content and antioxidant activities of grape and fruit juice products in the Korean market were examined The total phenolic content was measured by the Folin-Ciocalteau method, and antioxidant activities were evaluated by FRAP and DPPH assays. The total phenolic content of the grape juice products were within the range $57.95{\sim}205.64\;mg/L$. Orange juice had the strongest antioxidant activity, apple juice the weakest, and grape juice was intermediate. Grape juice products exhibited a wide range of antioxidant activities. Especially, GU4, GU5, and GU9 exhibited about 80% of the DPPH radical scavenging activities, similar to the antioxidant activities by the FRAP assay. The antioxidant activities by FRAP and DPPH assays were well correlated with the total phenolic content of grape juice products (> 0.97).

• Korean Journal of Environment and Ecology
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• v.35 no.5
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• pp.490-502
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• 2021

This study was conducted to analyze the current status of fish fauna and characteristics of the fish community according to the habitat of Woraksan National Park, Korea. The spatially balanced sampling selected 20 stations from major streams of Woraksan National Park, and three surveys were conducted in each season. The physical environments of the habitat were mostly mountain streams (Aa), with large stones and gravels scattered over the stream. The average altitude of the habitat was 304.4 m, and the average depth of water was 40.3 cm, being less than 1 m in most cases, and the river water level was distributed from 3rd to 5th streams. The principal component analysis of the physical environmental factors by habitat showed that the substrate properties differed according to the altitude. The survey identified a total of 2,183 individuals in 16 species belonging to 7 families. The dominant species was Zacco koreanus(86.2%), and the subdominant species was Rhynchocypris oxycephalus(3.8%). Pseudopungtungia tenuicorpa, classified as the endangered wildlife II, was the first endangered legally protected species found in this survey. Analysis of the rank abundance curve model in the fish community showed the Zipf model at 9 out of 20 points, the Lognormal model in 3 points, and the Preemption model in 4 points. The remaining 4 habitats showed only one species and were not analyzed. The canonical correspondence analysis of 20 stations and fish species was performed to understand the characteristics of the fish community according to environmental factors. The fish communities were divided according to differences in habitat environment by the altitude.