• Korean Journal of Environment and Ecology
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• v.26 no.3
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• pp.367-373
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• 2012

Population ecology (Ecological characteristics) of Squalidus japonicus coreanus from the Namhan River(Yangpyeong-gun Yangpyeong-eup Changde-ri), Gyeonggi-do, Korea were investigated from January to December 2011. Short barbel gudgeon inhabits habitats run of the lower river. The stream bed was mostly covered sand. Their current velocities were 0.14~1.38m/sec and depths were 80~120cm. The sex ratio of female to male was 1 : 0.82. It is presumed that the spawning season is from June to July and water temperatures were $18.5{\sim}24.3^{\circ}C$. Sexually matured individuals appeared over the two year of age. Frequency analysis of total length indicated that the group with 34~50mm in total length was one year old, the 51~74mm was two years old, and the group over 75mm was three years old. The average number of eggs in the ovaries was estimated as 1,871 per matured female. Stomach content of S. japonicus coreanus were Cyanophyta, Chlorophyta, Bacillariophyta, Rotatoria, Crustaceae, Copepoda, Ephemeroptera, Diptera, and Nematoda. omnivorous, mainly feeds on benthic invertebrates such as chironomidae larvae.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.2
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• pp.189-193
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• 2012

This experiment was conducted to study variations of serum testosterone and seminal characteristics of Markhoz male goats. Blood samples were obtained via jugular vein, and semen was collected by using an artificial vagina from 14 fertile male goats (2-3 years of age), at 15-day intervals starting on 15 July and ending on 30 October 2010 (during breeding and non-breeding season). Semen volume, total sperm (volume${\times}$concentration), live sperm (%), abnormal sperm (%) and semen pH were significantly superior during the late summer and early autumn (breeding season). Variation of sperm density, motility and progressive motility was not significant during the sampling period. The results presented show that the lowest and highest levels of lactate dehydrogenase in the seminal plasma were recorded in late October (2.82 U/ml) and in late August (4.81 U/ml), respectively. Moreover, the study indicated that the serum testosterone concentration was higher during late summer and early autumn (p<0.05) than at any other of sampling period. There were negative correlations between volume and sperm density (-0.135, p<0.05), and positive correlations between volume and percentage live sperm (0.224) and percentage progressive motility (0.194, p<0.01). Sperm density was correlated with live sperm (0.200, p<0.05) and progressive motility (0.202, p<0.01). The correlation between live sperm and progressive motility was 0.554 (p<0.01). Furthermore, the results in this study indicated a significant positive correlation between live sperm and LDH (0.450) and a negative correlation between sperm density and LDH concentration (-0.272) (p<0.01). Significant, but positive correlations were found between sperm motility and LDH (0.542) and testosterone concentration (0.522), respectively (p<0.05). In conclusion, this study demonstrated that the best obtained semen was collected in late summer (during decreasing photoperiod) and early autumn (September and October). This also coincides with the natural breeding season of Markhoz goats in Iran.

• Journal of Ecology and Environment
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• v.38 no.1
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• pp.57-65
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• 2015

A natural mixed stand of Phragmites australis and Phacelurus latifolius was studied to clarify the distribution properties in a microsite in a tidal flat of Suncheon Bay. The height, density, and biomass of the shoots, as well as the biomass of the root system, were monitored for both species along with the altitude on a mound from June 2010 to October 2013. Firstly, the mean height and dry weight of both species were similar during the growth season. However, individual variations of the sizes of plants in the same species were noticeable. Secondly, the density and dry weight per unit area of P. latifolius increased, but that of P. australis decreased with the altitude on the mound. Thirdly, the root system (rhizomes and roots) of P. latifolius was mostly located in the upper layer (up to 20 cm depth), while that of P. australis was in the lower layer (over 70 cm depth) of the sediment. The roots of P. australis penetrated to the lower parts of the water table, while the roots of P. latifolius did not make contact with free water of the sediment. Fourthly, the removal of the shoot in the early growth season led to a visible reduction of biomass in the late growth season. The reduction rate was larger in P. latifolius than in P. australis. Lastly, in the area where the mound was removed, the density of P. australis increased in the first two years (2010-2011) and was highly sustained inthe last two years (2012-2013). However, the density of P. latifolius was low, and this plant was distributed at the edge of the mound only.

• Korean Journal of Environment and Ecology
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• v.26 no.5
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• pp.780-786
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• 2012

A trenching method was used to determine the contribution of root respiration to soil respiration in Quercus acutissima forest in the vicinity of Gongju, Chungnam Province, Korea. $CO_2$ efflux in soil respiration plot($R_{control}$, $R_c$) and microblal respiration plot($R_{trenched}$, $R_t$) in Q. acutissima forest were measured from June 2011 to May 2012 by using IRGA soil respiration analyzer. Seasonal $CO_2$ efflux in $R_c$ and $R_t$ were higher in summer season than in winter season. In August, maximun $CO_2$ efflux in $R_c$ and $R_t$ was 1.345 and 0.897 g $CO_2\;m^{-2}\;hr^{-1}$, respectively. $CO_2$ efflux in $R_t$ was lower by 33.31% than that in $R_c$(P<0.05). In January, $CO_2$ efflux in $R_c$ and $R_t$ was 0.097 and 0.032g $CO_2\;m^{-2}\;hr^{-1}$, respectively. $CO_2$ efflux in $R_t$ was lower by 67.01% than that in $R_c$(P<0.01). The amount of annual $CO_2$ efflux from $R_c$ and $R_t$ was 4.320, 2.834kg $CO_2\;m^{-2}\;yr^{-1}$, respectively. There was a significant correlations between soil temperatures and soil respiration. Contribution of root respiration to total soil respiration in this Q. acutissima forest was 34.40%.

• Journal of agriculture & life science
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• v.46 no.6
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• pp.51-57
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• 2012

This study was carried out to analyze chemical compositions of the fog water of a forest area, Jinju and to provide basic information for establishing measures on the acid fog water of forest area. The results are as follows: The pH of fog water was 4.3 in 2010, whereas the pH in 2011 was 4.0. The electrical conductivity of the fog water was $477.2{\mu}s$ in 2010, and $562.7{\mu}s$ in 2011. Among the anions, the concentration of $NO^{3-}$ was the highest, which recorded 267.1 mg/L in spring season and 279.1 mg/L in summer season, followed by $SO{_4}^{2-}$ at the concentration of 177.2 mg/L in spring season and 198.6mg/L in summer season. In autumn and winter, the concentration of $NO^{3-}$ was highest as 217.7 mg/L and 237.9 mg/L, respectively and followed by $SO{_4}^{2-}$, which concentration was 164.2 mg/L in autumn season and 190.1 mg/L in winter season (p<0.05). Among the cations, the concentration of $Ca^{2+}$ was 221.3 mg/L in spring and 233.7mg/L in summer, followed by $Na^+$ at 125.1 mg/L in spring season and 131.7 mg/L in summer In autumn and winter, the concentration of $Ca^{2+}$ was highest at 196.8 mg/L and 198.8 mg/L, followed by $Na^+$ at the concentration of 97.1 mg/L in autumn and 117.2 mg/L in winter (p<0.05). The pH of the fog rain that causes acid mist showed the correlation with $Ca^{++}$ (1% of level), $EC(r=-0.9861^{**})$, $NO^{3-}$ ($r=-0.9677^{**}$), and $SO{_4}^{2-}$ ($r=-0.9510^{**}$). The regression equation on the factors affecting the generation of acidic fog rain was estimated to be a $Y(pH)=6.4627+0.9723X_2(EC)+0.9364X_4(NO_3{^-})+0.9044X_5(SO{_4}^{2-})+0.8049X_{10}(Ca^{2+})+0.6709X_8(K^+)\;(r^2=0.8787)$.

• Korean Journal of Remote Sensing
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• v.31 no.1
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• pp.11-20
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• 2015

This study aimed to investigate the canopy growth conditions and the accuracy of phenological stages of paddy rice using ground-based remote sensing data. Plant growth variables including Leaf Area Index (LAI) and canopy reflectance of paddy rice were measured at the experimental fields of Chonnam National University, Gwangju, Republic of Korea during the crop seasons of 2011, 2012, and 2013. LAI values were also determined based on correlations with Vegetation Indices (VIs) obtained from the canopy reflectance. Three phenological stages (tillering, booting, and grain filling) of paddy rice could be identified using VIs and a spatial index (NIR versus red). We found that exponential relationships could be applied between LAI and the VIs of interest. This information, as well as the relationships between LAI and VIs obtained in the present study, could be used to estimate and monitor the relative growth and development of rice canopies during the growing season.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.417-417
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• 2012

본 연구에서는 충청북도 보은군 수한면에 위치한 거현천의 사우교 지점에서 유량조사, 유사량 조사, 하상 퇴적물 조사를 실시하여 유량-총유사량 관계곡선식을 산정하였다. 총유사량 산정은 수정 아인쉬타인 방법을 적용하였으며, 2011년 홍수기에 4개의 호우사상에 대하여 16회 유량 및 유사량 조사를 실시하였다. 총유사량 산정의 실제적인 계산은 한국건설기술연구원에서 개발한 MODEIN 프로그램을 이용하였다. 사우교 지점 실측자료를 바탕으로 개발된 유량-부유사량 관계 곡선식은 $_s=2.4386Q^{1.9939}$이고, 결정계수 $R^2$=0.8307로 산정되었다. 유량-총유사량 관계곡선식은 $Q_s=3.1341Q^{2.0002}$이고, 결정계수 $R^2$=0.8599로 산정되었다. 본 연구를 통해 제시된 사우교지점의 유량-총유사량 관계식은 거현천의 기초자료로 활용될 것으로 사료된다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.5
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• pp.581-588
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• 2019

A long-term trend analysis of cold water masses along eastern coast of South Korea was performed during summer, based on wind speed, wind direction, and sea surface temperature (SST) data. Wind data collected over a 22-year period (1997-2011) were compared with another set of data collected over the successive 7-year (2012-2018), highlighting a general decrease in the frequency and speed of south winds. However, both the frequency and speed of these winds have been higher in June between 2012-2018, rather than between 1997-2011. The cold water season between July and August was faster during the 7-year period; moreover, the SSTs registered around Gangneung (EN) rose by $0.5^{\circ}C- 1.8^{\circ}C$, while those around Yeongdeok (EC) and Gijang (ES) increased by only $0.1^{\circ}C-0.3^{\circ}C$. The number of cold water days during the 7-year period, compared to those recorded during previous years (1990-2011, satellite SST data by NOAA/AVHRR), decreased in the proximity of Yeongdeok and Gijang, but increased in the proximity of Kangneung. Additionally, the number of cold water days around Kangneung, Yeongdeok, and Gijang increased in June highlighting a geographical and temporal change in the occurrence of cold waters. These observation can be explained by variations in the pressure distribution that should have weakened the East Asian monsoon, affecting the direction and speed of winds that regulate the flow of cold waters.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.25 no.1
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• pp.75-83
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• 2012

Objectives : The purpose of this study is to research the effect of bloodletting therapy and Alunitum-spread at palatine tonsil in acute tonsillitis. Methods : We reviewed medical records of 61 young patients of acute tonsillitis who had taken bloodletting therapy and Alunitum-spread from May 2003 to March 2011 in Samsung oriental medicine clinic. Results : There were 39 boys and 22 girls. Between 5 and 6 years-old group was more than the others. Between 3 and 4 days group was the first in duration of disease. Winter was the first and then spring, fall and summer in distribution of season. Between 9 and 10 days group was 22 patients, which was the first in duration of treatment. it was the first to have no history of acute tonsilitis group, and then cold, allergic rhinitis, laryngopharyngitis, acute tonsillitis and tympanitis. There were 41 patients who came to Samsung oriental medicine clinic the first and then western clinic, home remedy and other oriental clinic. Sore throat was the first sympton and then runny nose, high fever, nasal congestion and cough in companied symptom. Conclusions : Bloodletting therapy and Alunitum-spread were useful to improve acute tonsillitis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.6
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• pp.716-722
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• 2012

The larval occurrence of the red snow crab Chionoecetes japonicus was investigated near Dokdo in the East Sea of Korea, and the larval timing of the genus Chionoecetes in world oceans was reviewed. C. japonicus larvae were collected seasonally at 12 stations in February, May, August, and November in 2011. A Bongo net with a 303 mesh was deployed with a double oblique tow. Larvae appeared from February to August, but no larvae were found in November. Zoea I occurred at nine stations with a few zoea II in February, and were found until August. The larval densities in February were high near the northern. In May, megalopa were found at eight stations with a few zoea II. No larvae were caught in November. The larval abundance in the research area peaked in February. Overall, the larval duration of the genus Chionoecetes in the world's oceans persisted for a long time, and Chionoecetes larvae occurred during the warm season in each area. The cold temperature at the sea bottom, where gravid females are found, may prolong larval production along the distribution range of the genus Chionoecetes.