• Title/Summary/Keyword: Western coast

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Ecological Studies on the Coastal Plants in Korea -On the Sand Duen Vegetation of the Western Coast- (韓國海岸植物의 生態學的 硏究 - 西海岸의 沙丘植生에 關하여 -)

  • Lee,Woo Tchul;Sang-Keun Chon
    • The Korean Journal of Ecology
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    • v.7 no.2
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    • pp.74-84
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    • 1983
  • The dominant species of the sand vegetation in the western coast of Korea were Carex pumila, Ischaemum antheporoides, Calystegia soldanella, Carex kobomugi and Imperata cylindrica var. koenigii. The salt content of the sand dune soil and of the atmosphere of surveyed areas ranged from 3.93 to 13.86 mg% and from 25.81 to 168.86mg% respectively. Between the salt content of the atmosphere and that of the soil positive relationship was found. Species density and Simpson's index increased with the distance from the coast, the former was exponential, however, the latter was linear. The composition of biological types in the investigated stands were H-D4-R1-3-e or H-D4-R1-3-t. Relative numbers of psammophytes and rhizome psammophytes decreased with the distance from the coast, but those of other plants increased. The standing crop of the sand dune vegetation ranged from 0.04 to 491.64g/m2 and the average 27.77g/m2. This was varied as the stands and showed a linear increment as the distance from the coast was increased. The salt content of atmosphere significantly affected the density, T/R ratio in the standing crop and Simpson's index. The salt content of soil showed similar tendency on the density and the T/R ratio.

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Species Composition and Biomass of Marine Algal Community on the Mid-Western Coast of Korea (서해 중부 연안 해조군집의 종조성과 생물량)

  • 김영환
    • Journal of Plant Biology
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    • v.38 no.4
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    • pp.389-398
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    • 1995
  • The species composition and biomass of intertidal benthic algae at 12 widely dispersed stations representative of mid-western coast of Korea were studied. A total of 151 species of marine algae including 19 Cyanophyta, 20 Chlorophyta, 32 Phaeophyta and 80 Rhodophyta is listed. Three species were found at all 12 stations: Sargassum thunbergii, Stylonema alsidii and Gracilaria verrucosa. Biomass per unit area exhibited a wide range of variation, ranging from a low of 41 g dry $wt{\cdot}m^{-2}$ at both Paeksajang and Taechon to a high of 549 g dry $wt{\cdot}m^{-2}$ at Uihangri, the northernmost station of the study area. The latter value is higher than those reported from any other stations in western coast of Korea. Biomass was composed largely of Phaeophyta at nearly every station. Sargassum thunbergii was dominant over the study area. The distribution of Corallina spp., however, is disjunct, since those occur as dominant species in biomass at the northern stations and to a lesser extent at the southern stations, but are nearly absent from the middle part of the study area.

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Seasonal Characteristics of Phytoplankton Dynamics and Environmental Factors in the Coast of Mara-do and U-do, Jeju Island, Korea

  • Affan, Abu;Lee, Joon-Baek
    • ALGAE
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    • v.19 no.3
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    • pp.235-245
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    • 2004
  • A study on seasonal characteristics of phytoplankton dynamics and environmental factors was carried out at four stations including Mara-do and U-do located in the western and eastern coast of Jeju Island in southern Korea from April 2003 to March 2004. Out of 101 phytoplankton species identified, 84 belong to Bacillariophyceae, 9 Dinophyceae, 6 phytoflagellates and 2 coccolithophorids, and the highest value of species diversity was observed in April. Phytoplankton was more abundant at the western coast than at the eastern coast from March to September and its highest abundance was 49.24 ${\times}$ 10$^3$ cells L$^{-1}$ at Mara-do in July. The pennate diatoms were more abundant at the western coast than at the eastern coast with the highest abundance of 38.75 ${\times}$ 10$^3$ cells L$^{-1}$ at Mara-do in July, and during this period Nitzschia longissima contributed 68.5% of the total phytoplankton abundance. Naviculaceae was more abundant at Gosan (western coast) in November when Stauroneis membranacea represented 80.1% of the abundance. Leptocylindrus dances contributed 49.4% of the abundance at U-do in November. Dinophyceae was more abundant at U-do in August. Water temperature and pH fluctuated from 11.7${^{\circ}C}$ to 27.1${^{\circ}C}$ and from 7.31 to 8.70, respectively. Water temperature of Mara-do was about 1-2${^{\circ}C}$ higher than the other stations. Salinity varied from 30.4 to 35.0 psu with the minimum in rainy season and the maximum at the end of winter. The concentration of NH$_4$-N, NO$_3$-N, NO$_2$-N, PO$_4$-P and SiO$_2$-Si ranged 0.07-6.79, 1.0-62.0, 1.0-8.0, 1.0-7.0 and 7.0-191.0 $\mu$g-at L$^{-1}$, respectively. Chlorophyll a concentrations varied from 0.10 to 1.17 $\mu$g L$^{-1}$. NH$_4$-N concentrations were high at U-do from May to December, and at Mara-do from January to February. The high concentrations of NO$_3$-N were found at Mara-do from June to September and at U-do from January to May. The effects of various physicochemical parameters on the seasonal distribution and succession of phytoplankton population suggest that there is a classical pattern of phytoplankton dynamics in Jeju coastal waters.

A Way for Establishing Tsunami Scenario Data Base (지진해일 시나리오 DB 구축방안)

  • Lee Duk Kee;Ryoo Yonggyu;Yang JunMo;Kim Sukyung;Youn YoungHoon;Lee Jun Hee;Park Jongchan
    • 한국지구물리탐사학회:학술대회논문집
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    • 2005.05a
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    • pp.3-7
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    • 2005
  • Focal mechanism of the real and imaginary faults in the western coast of Japan has been assumed by examining the previous studies on the seismicity, seismic gap, fault behaviors, seismic zoning, and faults. In the area of no seismic information, the focal mechanism has been assumed to have the maximum influence on the tsunami height in the eastern coast of Korea. The tsunami height in a particular point of the eastern coast of Korea can vary up to 7 orders with the variation of the strike of the fault in a particular source point of the western coast of Japan with constant magnitude. Tsunami scenario DB including tile arrival times and tsunami heights has been constructing by using the assumed focal mechanism of the western coast of Japan. Tsunami warning system will be reinforced by using this tsunami scenario DB near future.

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A Way for Establishing Tsunami Scenario Data Base (지진해일 시나리오 DB 구축방안)

  • Lee, Duk-Kee;Ryoo, Yong-Gyu;Yang, Jun-Mo;Kim, Su-Kyung;Youn, Young-Hoon;Lee, Jun-Hee;Park, Jong-Chan
    • Journal of the Korean Geophysical Society
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    • v.8 no.2
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    • pp.93-96
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    • 2005
  • Focal mechanism of the real and imaginary faults in the western coast of Japan has been assumed by examining the previous studies on the seismicity, seismic gap, fault behaviors, seismic zoning, and faults. In the area of no seismic information, the focal mechanism has been assumed to have the maximum influence on the tsunami height in the eastern coast of Korea. The tsunami height in a particular point of the eastern coast of Korea can vary up to 7 orders with the variation of the strike of the fault in a particular source point of the western coast of Japan with constant magnitude. Tsunami scenario DB including the arrival times and tsunami heights has been constructing by using the assumed focal mechanism of the western coast of Japan. Tsunami warning system will be reinforced by using this tsunami scenario DB near future.

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Analysis of the Effects on the Southeastern Coast of Korea by a Tsunami Originating from Hypothetical Earthquake in Japan (일본 지진공백역에서의 지진해일이 우리나라의 남동연안에 미치는 영향분석)

  • Kim, Do-Sam;Kim, Ji-Min;Lee, Kwang-Ho;Son, Byoung-Kyu
    • Journal of Ocean Engineering and Technology
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    • v.21 no.6
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    • pp.64-71
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    • 2007
  • The hypothetical earthquake located on the fault zone along the western coast of Japan, where sufficient time has elapsed since the last earthquake or an earthquake has not occurred yet, is known to possess significant potential energy. The possibility of earthquake activities occurring here in the future is high. It is expected that the resulting tsunamis will cause great damage to the East Sea coast of Korea and affect parts of the southern coast as well. In this study, tsunami that may be caused by a virtual earthquake that is expected in the hypothetical earthquake, along the western coast of Japan, will be estimated using numerical simulation. From this, the effect of the tsunami originating from the hypothetical earthquake on the southeastern coast of Korea will be evaluated by examining the water level rise due to the maximum water level rise and changing time, for each point along the southeastern coast. It will be possible to use the virtual results obtained like this as important basic materials in future disaster prevention plans and designs, for determining the direction of coastal development, for arranging seashore and harbor structures and to carry out wave resistant design for the southeastern coast of Korea.

Frequency and Characteristics of Typhoons Approaching the Korean-Peninsula (한반도에 내습한 태풍의 빈도 및 특성)

  • Yu, Hui-Jeong;Park, Jun-Il;Lee, Bae-Ho
    • Water for future
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    • v.16 no.4
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    • pp.253-257
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    • 1983
  • In an attempt to study the frequency and characteristics of typhoons which hit the Korean Peninsula a period of 40 years from 1946 through 1979 was covered to collect necessary data with respect to occurrence of typhoons and their influence Typhoons which occurred between 1959 and 1980 were grouped according to their treking routes and strengths for detailed analyses. The results are summarized as follow; 1. The average annual occurrence of typhoons in the western pacific ocean was found to be 28, only two of which attacked the Korean Peninsula. 2. The annual probabilities of typhoons attacking were 0.925 for one or more, 0.700 for twice or more and 0.323 for there times or moro. 3. The monthly probabilities were found to be 0.228 in July, 0.434 in August and 0.194 in September. 4. An half of the typhoons which hit the Korean Pennisula passed through the western coast and the rest through the southern and eastern coasts in similan proportions. 5. The western coast is hit most frequently in July and less afterwords, visa-vis the southern and the eastern coast. 6. The minimum SLP averaged 983 mb and ordered by the treking routes as S

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Distribution Characteristics of Black-faced Spoonbill Platalea minor in Western Coast of South Korea

  • Lee, Woo-Shin;Hur, Wee-Haeng;Rhim, Shin-Jae
    • The Korean Journal of Ecology
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    • v.24 no.4
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    • pp.219-222
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    • 2001
  • The study was conducted to get the basic information for proper protection and management of black-faced spoonbill and their habitats in western coast of South Korea. The species was observed in 8 sites of western coast of South Korea in spring 2000. We confirmed breeding of this species at least 4 pairs in Seokdo island. This island is considered likely to be an imortant breeding site together with Yodo island, Hambakdo island and Yokdo island. Also, we observed breeding of herring gull in Seokdo island and small island nearby Boleumdo island for the first time in South Korea. Chilsando island, Cheonsuman bay and Gyeokyeolbiyeoldo island were considered as stopovers located on the Korean Peninsula route. The other sites were considered as summering sites of the black-faced spoonbill. Especially the birds were constantly observed from breeding season to postbreeding season in Seonduri and Yeochari of Ganghwado island. We have counted maximum 88 individuals gathered at Gaksiyeo in Seonduri and Yeochari on September 3, 2000. The species seemed to gather at these sites after breeding for migration to wintering ground in September. We also surveyed changes of the number of individuals as time of the ebb and flow on September 3 and 6, 2000, their time budgets were affected by the ebb and flow in these sites.

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Change of Mean Sea Level due to Coastal Development and Climate Change in the Western Coast of Korean Peninsula (해안개발과 기후변화로 인한 서해 연안해역의 평균해수면 변화)

  • Jung, Tae Sung
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.26 no.3
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    • pp.120-130
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    • 2014
  • Change of mean sea level in the western coast of Korean peninsula was estimated with the observed tide data of the KHOA. The cause of the change was investigated. Mean sea levels in the western coast have been changed due to coastal development projects in the coastal zone. The estimated variations, which are significantly different regionally, vary from -6.8 cm in Incheon to 38 cm in Gunsan. The changing rate of mean sea level occurred by natural factors such as global warming varies from 1.1 mm/year in the north to 4.4 mm/year in the south of western coast of Korean peninsula. In Jeju, sea level rise and rise of sea temperature showed a close relationship. Water temperature rise of one degree increases mean sea level to 0.6 mm in Jeju. Rising rate of mean sea level has increased rapidly after the mid-1980s.

The Trade Routes and the Silk Trade along the Western Coast of the Caspian Sea from the 15th to the First Half of the 17th Century

  • MUSTAFAYEV, SHAHIN
    • Acta Via Serica
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    • v.3 no.2
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    • pp.23-48
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    • 2018
  • The Silk Road usually implies a network of trade and communications that stretched from east to west and connected China and the countries of the Far East via Central Asia and the Middle East to the eastern Mediterranean, or through the northern coast of the Caspian Sea and the Volga basin to the Black Sea coast. However, at certain historical stages, a network of maritime and overland routes stretching from north to south, commonly called the Volga-Caspian trade route, also played a significant role in international trade and cultural contacts. The geopolitical realities of the early Middle Ages relating to the relationship of Byzantium, the Sassanid Empire, and the West Turkic Khaganate, the advance of the Arab Caliphate to the north, the spread of Islam in the Volga region, the glories and fall of the Khazar State, and the Scandinavian campaigns in the Caucasus, closely intertwined with the history of transport and communications connecting the north and south through the Volga-Caspian route. In a later era, the interests of the Mongolian Uluses, and then the political and economic aspirations of the Ottoman Empire, the Safavid State, and Russia, collided or combined on these routes. The article discusses trade contacts existing between the north and the south in the 15th and first half of the 17th century along the routes on the western coast of the Caspian Sea.