• Title/Summary/Keyword: coastal islands

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A Study on the Coexistence Direction of Sustainable Fishing Village and Marine Leisure Industry (지속가능한 어촌과 해양레저산업의 상생방향에 관한 연구)

  • Jin Park
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2021.11a
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    • pp.14-16
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    • 2021
  • This study is based on the circumstances such as accessibility of the Gyeonggi sea, marina facilities, limitations of fishery resources, and super-aging of fishing villages. This study is to identify the causes of conflicts in coastal spaces for the coexistence of fishing villages and marine leisure, and to revitalize islands in the metropolitan area. The purpose of the study is suggesting an efficient use of coastal space by utilizing the characteristics of the Gyeonggi sea area ‥‥

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The Morphological Changes of Deltaic Barrier Islands in the Nakdong River Estuary after the Construction of River Barrage (하구둑 건설 이후 낙동강 하구역 삼각주 연안사주의 지형변화)

  • Kim, Sung-Hwan
    • Journal of the Korean Geographical Society
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    • v.40 no.4 s.109
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    • pp.416-427
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    • 2005
  • This paper aims to investigate morphological changes of deltaic barrier islands in the Nakdong Estuary and especially their spatial variations after barrage construction. We analyzed shorelines, geometrical centroids, and areas to reveal the changes of barrier islands. Here, we suggest three interesting points from this study. First, each individual barrier island in the Nakdong estuary goes through a different stage of the geomorphic cycle. The frontal barrier islands such as Sinja-do and Doyo-deung grow because they are located in front of the gates of the barrage. Sediments in water out of the gates are moved to offshore and then reworked by coastal processes such as waves and tides. Second, on the contrary, Baekhap-deung located behind Doyo-deung now diminishes indicating that sediments mainly move to the frontal growing island. Third, there is no morphological change in several barrier islands far away from the main flow of the Nakdong river such as Jinwoo-do, Daema-deung, and Jangja-do. In conclusion, barrier islands in the Nakdong estuary show distinct spatial variations. As a barrier island is closer to the main channel or is in the frontal location, there happens a very dynamic change in the morphology of the island.

Spatial Distribution of Macrobenthic Communities on the Rocky Intertidal Zone of Specified Islands, Southern Coast of Korea (남해안 특정도서 암반조간대의 대형저서동물 군집의 공간분포)

  • Yang, Sehee;Yang, Hyosik;Lee, Changil;Seo, Chonghyun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.6
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    • pp.853-865
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    • 2022
  • In this study, from August to October 2019, we conducted a survey of the spatial distribution and dominant species of macrobenthos on the rocky intertidal zones of 38 specified islands distributed along the southern coast of Korea. On the basis of observation made using 50 × 50 cm quadrats, we identified a total of 80 species, among which, Mollusca were the most abundant fauna, with 54 species that accounted for 67.4% of the total, followed by Crustacea with 15 species (18.7%). The recorded numbers of Cnidaria, Porifera, and Echinodermata species ranged from 1 to 6. In terms of the regional patterns of species richness, specified islands in Yeosu were found to be the most species rich, supporting 61 species, whereas islands in Hadong, Namhae, and Chujado were found to have a similar level of species richness, ranging from 42 to 46 species. Islands in Boseong and Goheung were home to the fewest species, with only 29 species being recorded. At the sampling station scale, we noted a considerable difference in faunal richness, ranging from 6 (St. 6) to 33 (St. 20) species. Among the recorded species, Echinolittorina radiata was identified as the dominant species on 15 specified islands, with the next most abundant species being Tetraclita japonica, considered an indicator species of climate change, which was recorded on 11 islands. In terms of frequency, E. radiata, found on 36 islands, was identified as the most frequently occurring species, followed by Reishia clavigera (30 islands), Mytilisepta virgata (29), Nerita japonica (28), Ligia. exotica (27), and Littorina brevicula (26). Of the 80 species identified, 9, 4, and 2 species of Mollusca, Crustacea, and Cnidaria, respectively, are classified as Marine fauna of accepted foreign export, whereas 50 are Red List species, 44 are species of Least Concern, 3 are Data Deficient species, and 1 species was not evaluated. However, during the survey, we found no Near Threatened or Not Applicable species. On the basis of the findings of this survey, it would appear that the abundance and richness of macrobenthic fauna inhabiting the rocky intertidal zones of specified islands along the southern coast of Korea differ according to different habitat conditions, particularly with respect to the duration of exposure and the extent and properties of the substrata. The findings of this study will provide baseline data for future monitoring and management of specified islands in Korea.

Sea-level Change and Coastal Erosion (해수면 변화와 해안 침식)

  • Jeon, Dong-Chull
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.7 no.4
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    • pp.289-304
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    • 1995
  • Time series of the relative sea levels at the selected tide-gauge stations in the North Pacific and historical aerial photographs in the Hawaiian Islands are analyzed. Long-term rising trend of sea level ranges from +1 to +5 mm/yr at most of the stations, which is primarily due to global warming and tectonic motion of the plates. The annual and interannual fluctuations of sea level result from the thermal expansion/contraction of sea-surface layer due to the annual change of the solar radiation and possibly from a coupled ocean-atmosphere phenomenon associated with an ENSO event, respectively. Sea-level changes in three different time-scales (linear trend. annual oscillation, and interannual fluctuation) and their quantitative contribution to the shoreline changes as a result of long-term cross-shore sediment transport arc hypothesized.

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Current progress in development of full 3D earth model for integrated ray tracing simulation of planetary disk averaged spectra

  • Ryu, Dong-Ok;Jung, Kil-Jae;Oh, Eun-Song;Ahn, Ki-Beom;Jeong, Soo-Min;Jeong, Yu-Kyeong;Yu, Jin-Hee;Lee, Jae-Min;Hong, Eric(JS);Kim, Sug-Whan
    • Bulletin of the Korean Space Science Society
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    • 2008.10a
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    • pp.28.1-28.1
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    • 2008
  • Detection of spectral bio-signatures from extra terrestrial planets has received an increasing attention from the astronomy and space science communities in recent years. In an attempt to better-understand disk averaged spectra of the only know terrestrial planet i.e. Earth, we are constructing a scale-able 3D earth model with surface reflectance and scattering properties. The USGS coastal line data were used to form coastal line segments and they were then stitched to generate continuous coastal lines to represent major continents and large islands. As the first stage of model verification, wavelength dependent ocean and land reflectance data and scattering characteristics were defined over the land and sea surfaces respectively. We then performed ray tracing based imaging and radiometric transfer simulations using a hypothetical optical payload receiving the reflected and scattered sun lights from the earth. The model concept, computational details, the simulation results are discussed as well as the future development plan.

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A Practical Application of Multiple Wave Models to the Small Fishery Harbor Entrance

  • Jung, Jae-Hyun;Lee, Joong-Woo;Jeon, Min-Su;Kang, Seok-Jin
    • Journal of Navigation and Port Research
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    • v.31 no.7
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    • pp.579-587
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    • 2007
  • Samchunpo(Sin Hyang) Harbor is located in the bay of Sa Chun, the central south coast of Korean peninsula. The harbor and coastal boundaries have been protecting by natural coastal islands and shoals. Currently, The Sin Hyang harbor needs maintenance and renovation of the sheltered structures against the weather deterioration and typhoon damages. Consequently to support this, the calculation of accurate design wave through the typhoon wave attack is necessary. In this study, calculation of incident wave condition is simulated using steady state spectrum energy wave model(wide area wave model) from 50 years return wave condition. And this simulation results in wide offshore area were used for the input of the extended mild slope wave model at the narrow coastal area. Finally, the calculation of design wave at Sin Hyang harbor entrance was induced by Boussinesq wave model(detail area wave model) simulation. The numerical model system was able to simulate wave transformations from generation scale to shoreline or harbor impact. We hope these results will be helpful to the engineers doing placement, design, orientation, and evaluation of a wide range of potential solutions in this area.

Emissions of Sulfur Compounds and The Significance of Their Cycling in the Western Korea Sea (서해지역을 중심으로 한 자연적 황화합물의 배출과 순환에 대한 연구)

  • 김기현;이강웅
    • Journal of Environmental Health Sciences
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    • v.24 no.3
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    • pp.77-86
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    • 1998
  • The concentrations of atmospheric dimethylsulfide (DMS) and the relevant environmental parameters were measured as part of the 3rd year project (August 1997-July 1998) to investigate the long range transport of atmospheric pollutants (LRTAP) between China and Korea. The main purpose of this study was to derive the contribution of natural sulfur emissions (represented by oceanic DMS fluxes) in estimating the total budgets of sulfur transported across the Yellow Sea. To this end, DMS concentrations were determined from the two western coastal monitoring sites (Cheju and Kang Hwa islands) during three field intensive experiments covering fall, winter, and spring seasons. From these series of experiments, we found that DMS concentrations of Cheju and Kang Iffwa were averaged at 74 $\pm$ 49.5 (range: 19~282 pptv (N=81)) and 63.7 $\pm$ 35.1 (range:25.8~131 pptv (N=19)), respectively. By combining these 3rd year data with those measured previously from the 2nd year, we were able to derive some general pictures of seasonal distribution patterns of DMS. Although DMS data were difficult to derive relationships with other parameters determined simultaneously, they were rarely exhibiting good correlations with temperature or wind speed. The oceanic flux of DMS for the western coastal regions of Korea, when estimated based on our data from two islands, was found on the range of 8.8~12.2 GgS/yr. By considering the relationship between DMS and non-seasalt sulfate, we could also provide rough estimate of relative significance of natural emissions of sulfur. If oceanic DMS emitted from those regions is entirely converted to sulfate, it could represent 10 to 25% of total sulfur budgets in the western Sea of Korea.

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Distributions of Organic Matter and Trace Metals in Intertidal Surface Sediment from the Mokpo-Haenam Coast (목포-해남 연안 조간대 퇴적물중 유기물 및 미량금속 분포 특성)

  • Hwang, Dong-Woon;Kim, Pyoung-Joong;Jung, Rae-Hong;Yoon, Sang-Pil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.4
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    • pp.454-466
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    • 2013
  • To evaluate the organic matter and trace metal pollution in intertidal sediment of the coastal zone, various geochemical parameters (grain size, ignition loss [IL], chemical oxygen demand [COD], acid volatile sulfide [AVS], and metals [Al, Fe, Cu, Pb, Zn, Cd, Cr, Mn, Hg, and As]) were measured for the intertidal surface sediment of the mainland and islands between Mokpo and Haenam in the southwestern coast of Korea. The surface sediments consist mainly of finer sediments, such as mud and silt. The concentrations of IL, COD, and trace metals in intertidal sediment were relatively high in the shoreline of the mainland than in that of islands and those in some stations exceeded the sediment quality guidelines (SQGs). Moreover, the concentrations of IL, COD, and trace metals (except As) in sediment showed relatively good positive correlations with mean grain size, indicating that the concentrations of organic matter and trace metals in intertidal sediment of the study region are dependent on grain size of sediment. Pollution evaluation for trace metals using geochemical assessment techniques, such as enrichment factor, geoaccumulation index, and SQGs, suggested that the intertidal sediments in the study region show light pollution with Cr and moderate pollution with As. More extensive interdisciplinary studies are required to determine the potential causes of As pollution in intertidal sediment.

Spatiotemporal Variations of Coastal Sediment Transport at Barrier Islands in the Nakdong River Estuary (낙동강 하구 주요 연안사주에서 표층표사의 시.공간적 변화)

  • Jeon, Yong-Ho;Yoon, Han-Sam;Lee, Kyung-Seon
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.16 no.2
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    • pp.161-168
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    • 2010
  • We conducted a field survey of the generation and development of the delta area of the Nakdong River estuary, Korea. To examine deposition and erosion of the barrier islands, we observed the spatiotemporal variations of sediment transport and quantitatively estimated the settling velocity of coastal sediment. For the field survey, we established two survey sites off the coasts of Jinu Island and Doyodeung, which had shown rapid variations in deposition and erosion. At these sites, we measured the net surface elevation change of the bottom level at approximately 1-month intervals. Main findings were summarized as follows. (1) Calculated daily deposition and erosion velocity during the observation period ranged from -1.39 to 3.56cm/day at Jinu Island and from -4.0 to 3.07cm/day at Doyodeung, respectively. (2) Although two typhoons passed by the study area during the observation period, the maximum net surface elevation was larger in October than during the passage of those typhoons.

Study on planetary boundary layer schemes suitable for simulation of sea surface wind in the southeastern coastal area, Korea (한반도 남동해안 해상풍 모의에 적합한 경계층 물리방안 연구)

  • Kim Yoo-Keun;Jeong Ju-Hee;Bae Joo-Hyun;Song Sang-Keun;Seo Jang-Won
    • Journal of Environmental Science International
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    • v.14 no.11
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    • pp.1015-1026
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    • 2005
  • The southeastern coastal area of the Korean peninsula has a complex terrain including an irregular coastline and moderately high mountains. This implies that mesoscale circulations such as mountain-valley breeze and land-sea breeze can play an important role in wind field and ocean forcing. In this study, to improve the accuracy of complex coastal rind field(surface wind and sea surface wind), we carried out the sensitivity experiments based on PBL schemes in PSU/NCAR Mesoscale Model (MM5), which is being used in the operational system at Korea Meteorological Administration. Four widely used PBL parameterization schemes in sensitivity experiments were chosen: Medium-Range Forecast (MRF), High-resolution Blackadar, Eta, and Gayno-Seaman scheme. Thereafter, case(2004. 8. 26 - 8. 27) of weak-gradient flows was simulated, and the time series and the vertical profiles of the simulated wind speed and wind direction were compared with those of hourly surface observations (AWS, BUOY) and QuikSCAT data. In the simulated results, the strength of rind speed of all schemes was overestimated in complex coastal regions, while that of about four different schemes was underestimated in islands and over the sea. Sea surface wind using the Eta scheme showed the highest wind speed over the sea and its distribution was similar to the observational data. Horizontal distribution of the simulated wind direction was very similar to that of real observational data in case of all schemes. Simulated and observed vertical distribution of wind field was also similar under boundary layer(about 1 km), however the simulated wind speed was underestimated in upper layer.