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Development of Geochemical Tracers to Identify a Specific Source Region of Mineral Dust in China and Preliminary Test of Their Applicability (중국 기원 광물성 먼지 입자의 지화학 추적자 개발 및 기초 적용연구)

  • Lee, Sojung;Hyeong, Kiseong;Kim, Wonnyon;Kim, Tae-Hoon
    • Ocean and Polar Research
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    • v.41 no.3
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    • pp.169-181
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    • 2019
  • The purpose of this study is to develop geochemical tracers to identify a specific source desert of mineral dust in China using the published data. In addition, we tested the applicability of these tracers to wet-deposits and soil samples collected in Jeju, Korea. Because of similarity in trace elemental compositions of mineral dust from the major arid regions in China, such as Taklimakan, West Ordos (Badain Jaran), East Ordos (Mu Us and Hobq), East Northern China (Horqin), West Northern China (Gurbantunggut), and Chinese Loess Plateau, there has been limited to the use of geochemical data for source identification. Here we propose the four (4) plots using combination of seven (7) geochemical variables as a source indicator to distinguish one from other source regions in China: $\frac{Y}{Tb_N}$ vs. $\frac{Th}{{\Sigma}REE_N}$, $\(\frac{La}{Gd}\)_N$ vs. $\frac{Y}{{\Sigma}REE_N}$, $\frac{Th}{Tb_N}$ vs. $\frac{Y}{Nd_N}$, and $\frac{Th}{Tb_N}$ vs. $\(\frac{Ce}{Ce}\)_N^*$, where $_N$ and $\(\frac{Ce}{Ce}\)_N^*$ stand for values normalized to Post-Archean Average Shale composition and Ce anomaly, respectively. Mineral dusts from aforementioned six major deserts are distinguished one from the others by the combined use of these variables. Jeju rock and soil samples form a separate domain from Chinese mineral dusts in all four plots. In contrast, most of Jeju dust samples were comparable with the West Ordos desert (Badain Jaran) domain, indicative of strong influence of Badain Jaran dust in Jeju in spring season when the mineral dust was collected. A weak positive Ce anomaly in Jeju samples implies minimal local contribution. Our study suggests that the combination of $\frac{Y}{Tb_N}$ vs. $\frac{Th}{{\Sigma}REE_N}$, $\(\frac{La}{Gd}\)_N$ vs. $\frac{Y}{{\Sigma}REE_N}$, $\frac{Th}{Tb_N}$ vs. $\frac{Y}{Nd_N}$, and $\frac{Th}{Tb_N}$ vs. $\(\frac{Ce}{Ce}\)_N^*$ can be used to identify a specific source region of mineral dust in China as well as Jeju mineral particles.

Pelagic larval dispersal habits influence the population genetic structure of clam Gomphina aequilatera in China

  • Ye, Yingying;Fu, Zeqin;Tian, Yunfang;Li, Jiji;Guo, Baoying;Lv, Zhenming;Wu, Changwen
    • Genes and Genomics
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    • v.40 no.11
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    • pp.1213-1223
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    • 2018
  • Pelagic larval dispersal habits influence the population genetic structure of marine mollusk organisms via gene flow. The genetic information of the clam Gomphina aequilatera (short larval stage, 10 days) which is ecologically and economically important in the China coast is unknown. To determine the influence of planktonic larval duration on the genetic structure of G. aequilatera. Mitochondrial markers, cytochrome oxidase subunit i (COI) and 12S ribosomal RNA (12S rRNA), were used to investigate the population structure of wild G. aequilatera specimens from four China Sea coastal locations (Zhoushan, Nanji Island, Zhangpu and Beihai). Partial COI (685 bp) and 12S rRNA (350 bp) sequences were determined. High level and significant $F_{ST}$ values were obtained among the different localities, based on either COI ($F_{ST}=0.100-0.444$, P<0.05) or 12S rRNA ($F_{ST}=0.193-0.742$, P<0.05), indicating a high degree of genetic differentiation among the populations. The pairwise $N_m$ between Beihai and Zhoushan for COI was 0.626 and the other four pairwise $N_m$ values were >1, indicating extensive gene flow among them. The 12S rRNA showed the same pattern. AMOVA test results for COI and 12S rRNA indicated major genetic variation within the populations: 77.96% within and 22.04% among the populations for COI, 55.73% within and 44.27% among the populations for 12S rRNA. A median-joining network suggested obvious genetic differentiation between the Zhoushan and Beihai populations. This study revealed the extant population genetic structure of G. aequilatera and showed a strong population structure in a species with a short planktonic larval stage.

Mulseon-Jinsang Related Document Analysis in First Half of the 18th Century (18세기 전반 물선진상 관련 자료 분석 - 『진상별단등록』을 중심으로 -)

  • Jeon, Sang-wuk
    • Korean Journal of Heritage: History & Science
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    • v.47 no.4
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    • pp.178-191
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    • 2014
  • Jin-Sang is a local specialty donation to the palace. A local specialty donation to the palace is classified Jehyang, Bangmul, Mulseon, Medicine according to characteristic, when, use. Among these, Mulseon Jin-Sang is Most foods. And King was reduced Mulseon Jin-Sang in order to obtain a good image of the king. King Suk-Jong was frequently reduced Mulseon. But frequently changes of goods did not reflect to document. So type of goods, quantity is not clear in early 18th century. In 1728, King Yeong-Jo was published a Jingsangbyeldandngrok to clear type of goods, quantity. This book is written area, timing, quantity of Mulseon. Among these, type of goods, quantity are important. This book was written 176 kinds of goods. These goods was most of the fishery. And raw materials are largely accounted. In addition to processing the various creatures become like dried, pickled. By analyzing the regional allocation features, there are many types order by Gyeongsang-do, Hamgyeong-do. Gangwon-do. This area is faced east sea, so many fisheries have become records. In Gyeongsang-do, Cholla-do, these area were occupied a large portion of the fruit. And Jeju Island was assigned oranges. Finally, it has been assigned dried, pickled foods than living thing in distant area.

Spatial and seasonal distributions of the phototrophic dinoflagellate Biecheleriopsis adriatica (Suessiaceae) in Korea: quantification using qPCR

  • Kang, Hee Chang;Jeong, Hae Jin;Ok, Jin Hee;You, Ji Hyun;Jang, Se Hyeon;Lee, Sung Yeon;Lee, Kyung Ha;Park, Jae Yeon;Rho, Jung-Rae
    • ALGAE
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    • v.34 no.2
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    • pp.111-126
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    • 2019
  • The phototrophic dinoflagellate Biecheleriopsis adriatica is a small suessioid species characterized by a fragile thin wall. Although the morphology of this dinoflagellate is well established, there is currently little information available on its distribution and the environmental factors that influence this distribution. Thus, to investigate the spatial and seasonal distributions of the vegetative cells of B. adriatica in Korean waters, surface water samples were collected on a seasonal basis from 28 stations in the East, West, and South Sea of Korea and Jeju Island from April 2015 to October 2018, and abundances of the vegetative cells of B. adriatica were quantified using quantitative real-time polymerase chain reactions, for which we developed the species-specific primer and probe set. Simultaneously, major environmental parameters, including temperature, salinity, nutrient concentrations, and dissolved oxygen concentrations were measured. The vegetative cells of B. adriatica were detected at 20 of the 28 sampling stations: 19 stations in summer and 6 in autumn, although from no stations in either spring or winter. The ranges of water temperature and salinity at sites where this species was detected were $17.7-26.4^{\circ}C$ and 9.9-34.3, respectively, whereas those of nitrate and phosphate concentrations were not detectable-96.2 and $0.18-2.66{\mu}M$, respectively. Thus, the sites at which this species is found are characterized by a narrow range of temperature, but wide ranges of salinity and concentrations of nitrate and phosphate. The highest abundance of the vegetative cells of B. adriatica was $41.7cells\;mL^{-1}$, which was recorded in Jinhae Bay in July 2018. In Jinhae Bay, the abundance of vegetative cells was significantly positively correlated with the concentration of nitrate, but was negatively correlated with salinity. On the basis of these findings, it appears that the abundance of B. adriatica vegetative cells shows strong seasonality, and in Jinhae Bay, could be affected by the concentrations of nitrate.

Characteristics of Waterbird Community at Coastal Wetlands in the South and West Coasts, Korea (서·남해안 연안습지의 수조류 군집특성)

  • SHIN, YONG-UN;HAN, SEUNG-WOO;LEE, SI-WAN;HWANG, IN SEO;PARK, CHI-YOUNG
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.24 no.1
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    • pp.160-169
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    • 2019
  • The migration status of waterbirds inhabiting the 10 coastal wetlands in the south and west coasts (Jangbongdo, Muuido, Daecheoncheon estuary, Seocheon tidal flat, Yubudo, Gomso bay, Hauido, Jeungdo, Doam bay, Gangjin bay) was examined from May 2008 to March 2013. For the most dominant taxonomical group, shorebirds accounted for 37.5% of the number of species and 67.1% of the total population, followed in the order of dabbling ducks, herons, and seagulls. The dominate species were Calidris alpina, Larus crassirostris, Limosa lapponica, Charadrius alexandrinus, and Calidris tenuirostris. Shorebirds were observed most at Seocheon Tidal Flats and Yubudo Island, and dabbling ducks were found most in Doam Bay. Diving ducks were observed most at Gangjin Bay and seagulls were seen most frequently at Seocheon Tidal Flats. The ten coastal wetlands of the western and southern coasts were divided into three groups according to the similarity index of waterbirds (Ro). Group 1 was the area where dabbling ducks and diving ducks were dominant, group 2 was the area where shorebirds were dominant, and group 3 was the area where seagulls were dominant. It was evident that there were differences in species composition depending on the regional environments.

Prediction of Topographic Change in the Estuary of Nakdong River and Analysis of Its Contribution by External Force Condition (낙동강 하구 지형변화 예측 및 외력조건에 따른 기여도 분석)

  • Kim, Kang-Min;Lee, Joong-Woo
    • Journal of Navigation and Port Research
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    • v.43 no.1
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    • pp.64-71
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    • 2019
  • It is very important to understand the mechanism of estuary topographic changes for the study of estuary management and treatment methods. In this study, the effects from the land-side, such as rainfall, river discharge, sediment discharge, and sea side, such as tide, tidal current, wave and surface sediments related to the topographic changes of the Nakdong river estuary were investigated and analyzed. Based on the analyzed data, topographic modeling was performed to analyze the topographic change and contribution of external force conditions. As a result of numerical modeling, the topographic change showed that erosion that predominates in the water directly affected by the discharge of the estuary barrage. The deposition predominates in the indirectly affected tideland. As sediments moved along the water way being sorted and distributed by the wave, the deposition predominated in the front of the barrier island. Compared with the deposition dominance, which is the result of the topographic change prediction, the impact of each external force condition gives larger erosion. However, the combined impact of each external force condition showed deposition dominant. Therefore, the topographic changes of the Nakdong river estuary are considered to be the result of various complex external factors. The impacts of each external force condition show the different contribution to each comparison area. These results should be considered when establishing the estuary management method. It must be understood that this is the result of complex interactions.

Characteristics of Storm Surge by Forward Speed of Typhoon in the South Coast of Korea (태풍의 이동속도에 따른 한국 남해안 폭풍해일고의 특성)

  • Park, Young Hyun;Park, Woo-Sun
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.33 no.5
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    • pp.187-194
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    • 2021
  • The damage caused by typhoons is gradually increasing due to the climate change recently. Hence, many studies have been conducted over a long period of time on various factors that determine the characteristics of storm surge, and most of relationships have been discovered. Because storm surge is complexly determined by various factors, it often show different results and draw different conclusions. For this reason, this study was conducted to understand the various characteristics of storm surge caused by changes in the forward speed of typhoons. This study was carried out with a numerical model, and the effect of forward speed could be analyzed by simplifying other factors as much as possible. When forward speed is increased, storm surges caused by typhoons tended to increase gradually. The storm surge showed a wide and gentle increase at a slow speed, but a narrow and steep one at a fast speed. In the case of the same forward speed, it was found that the storm surge was significantly influenced by the water depth of actual sea area. It was confirmed that the change in forward speed after passing Jeju Island did not significant affect on the storm surge in the south coast of Korea.

Distribution and Habitat Characteristics of Odontobutis obscura, Endangered Species (멸종위기종 남방동사리의 분포와 서식처 특성)

  • Park, Sang-Hyeon;Kim, Jeong-Hui;Baek, Seung-Ho;Jo, Hyunbin
    • Korean Journal of Ecology and Environment
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    • v.54 no.2
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    • pp.79-86
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    • 2021
  • In this study, the distribution and habitat characteristics of Odontobutis obscura were investigated. It is a freshwater fish species which belongs to the Class I Endangered species as specified by the Ministry of Environment of South Korea. Sampling was conducted in the Sanyang Stream watershed between April and August of 2016. The Sanyang Stream watershed includes the Sanyang and Gucheon Streams, and their tributaries. Odontobutis obscura was caught at every sampling site, except sites 1~3, which are located in the lower part of the Sanyang Stream. Its habitat range extended from the headwaters to the lower parts of the stream that were not impacted by the South Sea. Salinity was the major factor limiting the distribution of O. obscura in the Sanyang Stream watershed. All individuals of O. obscura were caught in areas where the substrate composition was over 50% gravel. Furthermore, the substrate composition seems to be the most important habitat factor affecting spawning of O. obscura. Ecological studies of O. obscura are scarce, and this study is the first to report a detailed distribution for the species. Further studies on the physiology and ecology of O. obscura are essential for establishing preservation strategies for this endangered species.

Effects of Breed, Laying Age, and Egg Storage Period on the Vitality of Hatched Chicks in Korean Native Chickens (한국토종닭의 품종, 산란 연령 및 종란의 보관 기간이 병아리의 강건성에 미치는 영향)

  • Choi, Eun Sik;Sohn, Sea Hwan
    • Korean Journal of Poultry Science
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    • v.48 no.1
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    • pp.1-12
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    • 2021
  • We investigated the effects of breed, laying age, and egg storage period on the vitality of chicks using the Hwanggalsaek Jaeraejong, Korean Rhode Island Red, and Korean White Leghorn chicken breeds. Their eggs were collected during the early laying period (27~29 weeks) and late laying period (50~52 weeks) and were stored for 3 days, 7 days and 14 days. After the eggs hatched, the hatching time, production performance, and organ weight of chicks were investigated. IL-6 gene expression level and relative length of telomeres were analyzed to determine the physiological activity of the chicks. HSP gene expression level and heterophil to lymphocytes ratio were also analyzed to examine the degree of stress response in the chicks. The results showed that breed and laying age influenced the vitality of chicks, but the egg storage period did not. Korean Leghorn chicks were considered the weakest breed in terms of vitality owing to their low survival rate, small heart size, low physiological activity, and high stress response level. Although the survival rate of chicks produced in the early laying period was low, their high physiological activity and low stress response indicated that they had a high vitality than the chicks produced in the late laying period. In conclusion, to obtain chicks with high vitality, it would be desirable to select a high vitality breed and avoid the use of chicks produced in the late laying period.

An Analysis on Limited Warfare through the Falkland Islands Dispute (포클랜드제도 분쟁을 통한 제한전 분석)

  • Yang, Seong-sil;Lee, Hee-wan;Shin, Jin
    • Maritime Security
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    • v.3 no.1
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    • pp.211-235
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    • 2021
  • As a result of the Falkland Islands War from April 2 to June 14, 1982, Britain overcame severe economic depression and reclaimed the glory of the former British Empire by winning the war. On the other hand, Argentina was greatly affected by the collapse of a military dictatorship and the birth of a democratic government. This study suggests strategies for responding to maritime disputes that may occur in Dokdo Island in the future by applying "DIME on PMESII" to the Falkland Islands dispute. In particular, the study analyzes how DIME (diplomacy, information, military, and economy) capabilities have an effect as a means of the total national power of a country that effectively controls the disputed territory. Based on the results of this study, the response strategies related to the Dokdo maritime dispute are as follows. First, effective control over the disputed territory should be effectively maintained and strengthened like in Britain. This strategy inspires patriotism, supports the government during warfare, secures a just cause for war, and gains international support. Second, 'DIME on PMESII' was effective in modern warfare by focusing our DIME capabilities on the weaknesses of the other country's PMESII system. That is, wars are not won simply by the conflict of armed forces but by a nation's overall national strength, such as diplomatic, information, and economic capabilities. Third, appropriate strategies for neighboring countries are needed to overcome the possibility of limited warfare in the sea through preparations for Dokdo maritime disputes in the future.

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