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The Estimation of Environmental Capacity in the Gamak Bay Using an Eco-hydrodynamic Model (생태계모델을 이용한 가막만 해역의 환경용량 산정)

  • Kang, Hoon;Kim, Jong-Gu
    • Journal of Environmental Science International
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    • v.15 no.10
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    • pp.951-960
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    • 2006
  • The eco-hydrodynamic model was used to estimate the environmental capacity in Gamak Bay. It is composed of the three-dimensional hydrodynamic model for the simulation of water flow and ecosystem model for the simulation of phytoplankton. As the results of three-dimensional hydrodynamic simulation, the computed tidal currents are toward the inner part of bay through Yeosu Harbor and the southern mouth of the bay during the flood tide, and being in the opposite direction during the ebb tide. The computed residual currents were dominated southward flow at Yeosu Harbor and sea flow at mouth of bay, The comparison between the simulated and observed tidal ellipses at three station showed fairly good agreement. The distributions of COD in the Gamak bay were simulated and reproduced by an ecosystem model. The simulated results of COD were fairly good coincided with the observed values within relative error of 1.93%, correlation coefficient(r) of 0.88. In order to estimate the environmental capacity in Gamak bay, the simulations were performed by controlling quantitatively the pollution loads with an ecosystem model. In case the pollution loads including streams become 10 times as high as the present loads, the results showed the concentration of COD to be $1.33{\sim}4.74mg/{\ell}(mean\;2.28mg/{\ell})$, which is the third class criterion of Korean standards for marine water quality In case the pollution loads including streams become 30 times as high as the present loads, the results showed the concentration of COD to be $1.38{\sim}7.87mg/{\ell}(mean\;2.97mg/{\ell})$, which is the third class criterion of Korean standards for marine water quality. In case the pollution loads including streams become 50 times as high as the present loads, the results showed the concentration of COD to be $1.44{\sim}9.80mg/{\ell}(mean\;3.56mg/{\ell})$, which is the third class criterion of Korean standards for marine water quality.

Positive correlation water temperature increase with thermal front retrogression in the southern sea of Korea (남해 연안수의 수온상승과 수온전선 후퇴와의 상관성)

  • Kim, Yeong-Taek;Lee, Ho-Jeong
    • 한국지구과학회:학술대회논문집
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    • 2010.04a
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    • pp.122-123
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    • 2010
  • 2000~2009년 동안 격월로 관측한 수온 관측 자료를 분석하여 표층 수온이 10년 동안 약 $1{\sim}1.9^{\circ}C$ 상승하는 경향을 관찰하였다. 상승폭이 해역마다 약간의 차이를 보이고 있는데 부산해역은 약 $1.5^{\circ}C$, 여수해역은 약 $1.7^{\circ}C$, 제주북부에서도 약 $1.7^{\circ}C$의 상승폭을 보임으로서 남해 동쪽보다는 서쪽해역의 상승폭이 약간 높게 나타났다. 남해 연안수의 평균 수온이 증가하는 추세경향으로 미루어 볼 때 남해 수온전선이 약해지게 되어 결과적으로 연안쪽으로 밀릴 것으로 추정된다. 제주도 모슬포는 약 $1.9^{\circ}C$ 가 상승하였으며 제주도 성산포는 2004~2009년 동안 약 $1.2^{\circ}C$ 상승하는 추세를 보였다. 이와 같은 수온의 변동성은 조위관측소에서 관측된 수온에서도 확인할 수 있는데 부산은 $0.2^{\circ}C$/8년, 여수 $0.4^{\circ}C$/10년, 제주북부는 $1.5^{\circ}C$/10년, 모슬포와 성산포는 $1^{\circ}C$/6년, 서귀포는 $1.7^{\circ}C$/8년 상승폭을 보인다. 조위관측소의 수온 상승폭보다 한국연안해류조사의 수온 상승폭이 약간 높게 나타나고 있는데 이는 관측소의 위치가 해안가에 있는 반면 연안해류조사는 선박을 이용하여 외해쪽에서 수온을 관측하기 때문에 고온 고염의 대마난류(Tsushima Warm Current) 영향을 더 많이 받았기 때문으로 볼 수 있다. 해수의 수온 상승 현상은 증가율이 약간 낮기는 하지만 50m 수심에서도 나타나고 있다. 부산해역, 여수해역, 제주북부 해역은 모두 약 $1.2^{\circ}C$의 상승폭을 보였으며, 제주도 성산포는 약 $1.1^{\circ}C$인 반면, 모슬포 해역에서는 약 $1.5^{\circ}C$로 상승추이가 크게 나타났다. 이와 같이 남해 연안수가 표층과 저층에서 동반 상승했다는 것은 대마난류의 세력이 강해졌다는 것을 보여주는 지시자(indicator)로서 최근 제주도와 남부지방의 기후온난화와 관련이 있을 것으로 추정된다. 하지만 상승률은 관측기간이 길어질수록 작아지는 경향이 있기 때문에 남해의 물리적 특성 변화를 보다 명확히 규명하기 위해서는 좀 더 장기적인 자료가 필요하다.

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Classification of Climate Zones in South Korea Considering both Air Temperature and Rainfall (기온과 강수특성을 고려한 남한의 기후지역구분)

  • Park, Chang-Yong;Choi, Young-Eun;Moon, Ja-Yeon;Yun, Won-Tae
    • Journal of the Korean Geographical Society
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    • v.44 no.1
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    • pp.1-16
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    • 2009
  • This study aims to classify climate zones using Empirical Orthogonal Function and clustering analyses considering both air temperature and rainfall features in South Korea. When examining climatic characteristics of air temperature and rainfall by seasons, the distribution of air temperature is affected by topography and latitude for all seasons in South Korea. The distribution of rainfall demonstrated that the Yeongdong area, the southern coastal area and Jeju island have higher rainfall while the central area in Gyeongsangbuk-do is the least rainfall area. Clustering analyses of average linkage method and Ward's method was carried out using input variables derived from principal component scores calculated through Empirical Orthogonal Function analysis for air temperature and rainfall. Ward's method showed the best result of classification of climate zones. It was well reflected effects of topography, latitude, sea, the movement of surface pressure systems, and an administrative district.

Analysis on the Variability of Korean Summer Rainfall Associated with the Tropical Low-frequency Oscillation (적도 저주파 진동과 관련된 한반도 여름철 강수의 변동성 연구)

  • Moon, Ja-Yeon;Choi, Youngeun;Park, Changyong
    • Journal of the Korean Geographical Society
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    • v.48 no.2
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    • pp.184-203
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    • 2013
  • This study analyzes the variability of Korean summer rainfall associated with the tropical low-frequency oscillation using long-term observation data. From the EOF analysis, the first mode showed opposite phase between the South and the North Korea with the regime shift in rainfall variability since the mid-1990s. The summer precipitation over South Korea tends to increase in southern part during strong El Ni$\tilde{n}$o where the warm sea surface temperature extends to far eastern tropical Pacific. In weak La Ni$\tilde{n}$a, the increased precipitation directly influences from the western tropical Pacific to the mid-latitude. In June, the rainfall over South Korea is positively correlated with the Indian Summer Monsoon while in July, it is negatively correlated with the Western North Pacific Summer Monsoon. In August, highly negative correlation between the rainfall over South Korea and the Indian Summer Monsoon is found.

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Effects of the 1975 Haicheng Earthquake on the Korean Peninsula (1975년에 발생한 중국 해성지진이 한반도에 미친 영향)

  • 추교승
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1998.10a
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    • pp.210-221
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    • 1998
  • In the period from the year 1500 to 1980. at least 14 large earthquake with epicenters in the northeastern China and Yellow Sea were felt or destructive in the Korean Peninsula. The most sigmificant events among them were the 1668 July 25 Tancheng earthquake of mamnitude 8.5, and the 1975 Feb. 4 Haicheng earthquake of magnitude 7.3. The Haicheng earthquake of the year 1975 in am extraordinary one among those occurred in the northeastern China in the 20th century in the sense the Shake of the event affected all over the Korean Peninsula. The tremor was felt even at the southeastern tip of the Korea and northern part of Kyushu 700km far away from the epicenter. In order to see the variation and trend of the effect of the Haicheng earthquake on the Korean Peninsula, the two data sets of the northern and southern parts of the peninsula were merged into one combined data set. The spatial variation of intensity shows smooth decrease from the value 4 of the northwestern region near the source to the value 1 of the Cheju Island and Kjushu. However, there are four regions of locally high intensity value. They are the region along downstream of Abrok(Yalu) River with intensity 5, the region around Shinpo of intensity 4, the area comprising Seoul and Chuncheon Cities of intensity 4, and Pohang-Pusan area of intensity 3. We suppose that there might be three types of possible mechanisms. The first one is concerned with the lateral inhomogeneity of velocity in the crust caused by wide distribution of relatively fractured rock. The second one is related with reflections of surface waves caused by the crestal thinning effect at border regions of the Peninsular in contact with the Ulleung Basin and the Japan Basin. The third possibility is local site effect caused by thick Tertiary or Quaternary rocks and soil layers.

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The Origin/Destination Analysis of Container Cargo in International Passenger Terminals - Focused on Incheon Port - (국제여객터미널의 컨테이너화물 기종점 분석 - 인천항을 중심으로 -)

  • Moon, Gwang-Suk;Yoo, Hong-Sung;Kim, Youn-Sung;Lee, Dong-Won
    • Journal of Korea Port Economic Association
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    • v.27 no.2
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    • pp.195-215
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    • 2011
  • The purpose of this article is to provide data to be utilized for marketing to attract future container cargo to the Korea-China Car Ferry Service and to estimate container traffic for the development of the International Passenger Terminal to be newly built in the Incheon Southern Port. An analysis of container traffic through the Passenger Terminal of Incheon Port showed that the container throughput of Incheon Port comprised 20% of traffic. The export cargo traffic in the International Passenger Terminal, 71.4%, or 111,698 TEU of 156,284 TEU in total, was brought from metropolitan areas. To increase the container traffic of the car ferry service currently concentrated on the metropolitan areas, more endeavor is required to strengthen marketing competence to attract container traffic to other regions apart from the metropolitan areas as well as provide general services.

Taxonomic Revision of the Flounders (Pisces : Pleuronectiformes) from Korea (한국산 가자미아목 어류의 분류학적 연구)

  • Kim, Ik-Soo;Youn, Chang-Ho
    • Korean Journal of Ichthyology
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    • v.6 no.2
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    • pp.99-131
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    • 1994
  • The taxonomic revision of the flounders of the suborder Pleuronectoidei was made based on the specimens collected from the coasts of the Korean Peninsula from 1989 to 1993. The flounders of Korea are composed 34 species belonging to 24 genera and 4 families, and the keys to species, genera and families are provided with redescriptions and distributions. Three species of the flounders are found to be new to Korea : Tarphops oligolepis (Bleeker) of the family Paralichthyidae, Parabothus kiensis (Tanaka) of the family Bothidae and Pleuronectes pallasii Steindachner of the family Pleuronectidae. Laeops lanceolata, previously recorded in the Korean fish list, was found to be synonym of L. kitaharai. The fishes of the families Paralichthyidae and Bothidae were distributed in the Yellow Sea and the southern coast of Korea, while most of the flounder species of the family Pleuronectidae except Limanda yokohamae, Eopsetta grigorjewi, and Pleuronichthys cornutus were found along the eastern coast of Korea. It appears that Korean flounders are similar to those of Chinese and Japanese faunas which include tropical and temperate species without endemics.

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First Record of Two Perciform Fishes, Chelidoperca pleurospilus (Serranidae) and Parapercis muronis (Pinguipedidae) from Korea (한국산 농어목 어류 2 미기록종, Chelidoperca pleurospilus 및 Parapercis muronis)

  • Park, Jeong-Ho;Kim, Jin Koo;Choi, Jung Hwa;Chang, Dae Soo;Park, Jong Hwa
    • Korean Journal of Ichthyology
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    • v.19 no.3
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    • pp.246-252
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    • 2007
  • Two specimens (56.3~61.1 mm SL) of the serranid fish, Chelidoperca pleurospilus and 21 specimens (34.0~93.6 mm SL) of the pinguipedid fish, Parapercis muronis were collected around Jeju Island, southern Korea. C. pleurospilus is characterized by having five dark blotches along lateral line, truncated caudal fin, and scaleless interorbital space. P. muronis is characterized by having five oblique dark bands on body side, five spines on dorsal fin, and no notch between spinous and soft-rayed portions of dorsal fin. We describe these specimens as the first record from Korea, and propose the new Korean name, "Byeol-gak-si-dom" for the former and "Da-seosjul-yang-dong-mi-ri" for the latter.

Seasonal Variation in Fish Species Composition in Seagrass Bed of Aenggang Bay in the South Sea of Korea (남해 앵강만 잘피밭 어류의 월별 종조성 변화)

  • Lee, Seung Hwan;Lee, Yong Deuk;Shin, Min Gyu;Gwak, Woo Seok
    • Korean Journal of Ichthyology
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    • v.28 no.4
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    • pp.249-259
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    • 2016
  • Monthly variation in species composition was determined using fish samples collected by a beach seine between October 2013 and September 2014 in the eelgrass bed in Aenggang Bay, Namhae, Gyeongsangnamdo. A total of 3,174 individuals of 35 species, amounting to 3,137 g were collected. The dominant species was Gymnogobius heptacanthus, followed by Pholis nebulosa, Rudarius ercodes, Favonigobius gymnauchen and Hypodytes rubripinnis. Almost all fish collected were small in size or juveniles. Seasonal variation of species composition showed that the dominant species, used the shallow area of the eelgrass bed as a nursery ground and moved to a deeper water as they grew. Saurida elongata, Inimicus japonicus, Sphyraena pinguis, and Arothron hispidus, were first reported in an eelgrass bed in the southern coastal water.

Germ Cell Development During Spermatogenesis and Taxonomic Values in Mature sperm Morphology in Male Argopecten irradians irradians (Pteriomorphia: Pectinidae) in Southern Korea

  • Kim, Jin-Hee;Chung, Jae-Seung;Park, Young-Je
    • The Korean Journal of Malacology
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    • v.28 no.1
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    • pp.55-64
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    • 2012
  • Ultrastructural studies of germ cell development during spermatogenesis and taxonomic values in mature sperm morphology of Argopecten irradians irradians were investigated by transmission electron microscopic observations. In the early stage of spermatid during spermiogenesis, a few granules and proacrosomal granules are formed by the Golgi complex. In the late stage of spermatid during spermiogenesis, a proacrosomal vesicle becomes an acrosomal vesicle in the acrosome through spermiogenesis. The sperm is approximately $ 45-48{\mu}m$ in length including a jar-shaped sperm nucleus (about $1.45{\mu}m$ long), an acrosome (about $0.34{\mu}m$ long) and tail flagellum. The axoneme of the sperm tail shows a 9+2 structure. As one of common characteristics of mature sperm morphologies in Pectinidae species in subclass Pteriomorphia, mature spermatozoon consists of the cone-shaped acrosomal vesicle and subacrosomal material on the invaginated jar-shaped nucleus. The acrosomal vesicle of this species is composed of electron high dense opaque part (material) from the base to the tip, as have seen in the species in the subclass Pteriomorphia. Exceptionally, five mitochondria are found in the sperm midpiece of this species, unlike four in most species of Pectinidae in subclass Pteriomorphia. However, the acrosomal vesicle of spermatozoa of A. irradians irradians resemble to those of other investigated Pectinidae species in subclass Pteriomorphia. Therefore, we can use sperm morphology as a tool in the resolution of taxonomic relationships within the Pectinidae species. These morphological charateristics of acrosomal vesicle belong to the family Pectinidae in the subclass Pteriomorphia.