• Title/Summary/Keyword: coastal change

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Efficiency Assessment of Analysing Coastal Geomorphic Landscape Change by Satellite Image Interpretation (위성영상을 이용한 해안습지 지형경관 변화 분석의 효율성 평가)

  • 박의준;구자용
    • Journal of the Korean Geographical Society
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    • v.38 no.5
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    • pp.822-834
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    • 2003
  • It is difficult to analyse geomorphic landscape changes effectively by a field survey. A satellite image interpretation may play an important role to overcome such a problem. The purpose of this study is to assess the accuracy of different method to identify geomorphic landscape change by using satellite imagery. The study area is the Yongjong coastal wetland in which a huge man-made environmental change occured to build a new international airport in the past decade. These changes may be summarized that a coastal landscape has been changed to a terrestrial landscape, and also a natural landscape to a man-made landscape. In order to detect these changes, we applied three different satellite interpreting methods, including a binary change mask using band difference. a binary change mask using normalized band difference. and a binary change mask using NDVI. We concluded that a binary change mask using NDVI is the best method among three different methods analysing the coastal geomorphic-landscape changes.

Numerical Analysis for Wave Propagation and Sediment Transport with Coastal Vegetation (연안식생에 의한 표사이동 특성에 관한 수치해석)

  • Lee, Seong-Dae
    • Journal of Ocean Engineering and Technology
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    • v.21 no.5
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    • pp.18-24
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    • 2007
  • The environmental value of coastal vegetation has been widely recognized. Coastal vegetation such as reed forests and seaweed performs several useful functions, including maintaining water quality, supporting fish (and, thus, fisheries), protecting beaches and land from wave attack, stabilizing sea beds and providing scenic value. However, studies on the physical and numerical process of wave propagation, sediment transport and bathymetric change are few and far between compared to those on the hydrodynamic roles of coastal vegetation. In general, vegetation flourishing along the coastal areas attenuates the incident waves through momentum exchange between stagnated water mass in the vegetated area and rapid mass in the un-vegetated area. This study develops a numerical model for describing the wave attenuation and sediment transport in a wave channel in a vegetation area. By comparing these results, the effects of vegetation properties, wave properties and model parameters are clarified.

Coastal Topography and Shoreline Change in Gohyun Bay, Geojedo (거제 고현만 주변해역의 지형 및 해안선 변화 특성)

  • Kim Jong-Kyu;Kim Myong-Won;Lee Moon-Ock;Lee Yeon-Gyu
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2004.11a
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    • pp.137-142
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    • 2004
  • There has been considerable controversy over the change of coastal topography and shoreline by coastal erosion in Gohyun Bay, Geojedo. In this study, we analyzed aerial photographs and surveyed coastal topography and shoreline. Changes between years were identified using a GIS overlay analysis and field surveys with DGPS, Total Station and Echo Sounder. As a result, we were able to identify changes by coastal erosion in the area of Gohyun Bay, Geojedo.

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Research Perspectives for Developing Seawater Intrusion Indicators in Changing Environments with Case Studies of Korean Coastal Aquifers: A Review

  • Chang, Sun Woo;Kim, Il Hwan
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.44 no.4
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    • pp.465-482
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    • 2024
  • The global use of groundwater in coastal areas has increased. Events such as seawater intrusion (SWI) are expected to increase along with the acceleration of natural disasters owing to environmental changes such as climate change, resulting in large-scale damage worldwide. Current trends in the research of coastal groundwater and related natural disasters include testing and verifying technologies using major case studies from individual countries. We identified global research trends in coastal groundwater, related these trends to changing environments and climate, and confirmed the qualitative and quantitative growth of these studies. This study describes the theoretical background and techniques for coastal groundwater analysis and details regional-scale SWI indicators based on analytical and numerical studies. This review highlights recent technologies that consider uncertainty and promotes discussions on field data obtained using new technologies. Finally, the research findings and trends for a regional coastal aquifer in Korea are discussed to describe recent SWI approaches for groundwater resources.

A Study on the Management Planning for the Conservation and Environmentally Friendly Use of Korean Coastal Wetlands (우리 나라 연안습지의 보전과 환경친화적 관리방안에 관한 연구)

  • Park, Tae-Yoon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.2 no.3
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    • pp.64-73
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    • 1999
  • The purpose of this study is to establish the management plannings for the conservation and environmentally friendly use of Korean coastal wetlands. The function, economic value, and the necessity for the conservation of coastal wetlands are described. The current management status, Korean Governmental policies for the use of coastal wetlands, and their problems are surveyed and analysed. The management plannings for the environmentally friendly use of Korean coastal wetlands is suggested as follows: (1) The coastal wetlands need to be divided into 3 different regions based on PSR(Pressure, State, Response) of OECD. (2) Each region should be managed by appropriate management plans which are suggested in Chapter IV of this paper. Finally, in order to realize these management plannings the change of Governmental system and laws are suggested as follows: (1) The change of relevant laws is required. Additionally, each region should managed by proper governmental agencies. (2) The EIA(Environmental Impact Assessment) system should be improved. (3) The participation of regional people should be guaranteed in the decision making processes of the business and other important planning regarding coastal wetlands. (4) The system which primed the ecological value of coastal wetlands should be established.

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Strategic actions to enhance environmental regulation and management of a coastal community to mitigate climate effects

  • Mao, HAK;Lee, Young-Chan
    • Journal of Advanced Marine Engineering and Technology
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    • v.40 no.10
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    • pp.922-928
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    • 2016
  • Bearing in mind that global climate change is a rising issue, the coastal community of Prek Thnaot, Cambodia has been put on severe effects about natural disasters caused from poor infrastructure and agriculture dependence. This paper proposes to provide and guide a strategic action for the sustainable development path of coastal community in a more continuous manner including a robust resilience to impacts of climate change, natural disasters, and other risks. In doing so, this paper will help environmentally sound management and coastal resources sustainability being sound for socially and economically inclusive development. Proposed fourteen strategic actions for the research should be accompanying with the participation of and cooperation from the local coastal community. Based on the proposed strategic actions, it is critical that the local authorities and other key stakeholders need to accomplish. Providing a good insight for the central government, the strategic action is expected to integrate and prepare a management strategy plan for the local coastal community level. Therefore, this information can be applied to other coastal areas to promote and ensure sustainable protection and management of coastal resources.

Estimation of Historical Shorelines on a Coastal Reclaimed Land (II) : Shoreline Change Analysis (해안 매립지에서 과거 해안선의 산정 (II): 해안선변화 분석)

  • Kim, Baeck-Oon;Lee, Chang-Kyung
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.21 no.5
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    • pp.380-390
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    • 2009
  • This study was conducted as a part of investigating pre-reclamation shorelines from aerial photographs to estimate coastal land area at reclaimed lands (Anjeong industrial complex, Myeongji residental complex, and Noksan industrial complex), southeastern coast of Korea. To assess how the shorelines were suitable for the calculation of coastal lands, we constructed shoreline change data. Secondary ground control points were used to accomplish triangulation for old aerial photographs. Two kinds of shorelines were mapped; one was the shoreline based on approximately highest high water level (AHHWL) and the other was the high water line based on wet/dry signiture. These shorelines were consistent at artificial coast. Shoreline change data were built with a variety of levels of error due to detailed differences in the photograph scale, quality of image, type of ground control point and type of shoreline. Thus assessment of the pre-reclamation shorelines at the level of qualitative analysis for the trend of shoreline changes was satisfactory. Most of shoreline changes before reclamation in this study were associated with coastal development. Investigation of shoreline attributes in relation to aerial photographs allowed us to understand the shoreline changes.

Attenuation of High-Frequency Wave Energy Due to Opposing Currents

  • Suh, Kyung-Duck;Lee, Dong-Young-
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 1993.07a
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    • pp.20-25
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    • 1993
  • In coastal waters, more often than not, waves propagate on currents driven by tidal forces, earth’s gravity, or wind. There have been a number of studies for dealing with the change of wave spectrum due to tile presence of current. Based on the conservation of wave action, Hedges et al. (1985) have proposed an equation which describes the influence of current on the change of wave spectrum in water of finite depth. (omitted)

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Coastal Circulation and Bottom Change due to Ocean Resort Complex Development

  • Kim, Pill-Sung;Lee, Joong-Woo;Kim, Jeong-Seok
    • Journal of Navigation and Port Research
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    • v.36 no.7
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    • pp.585-590
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    • 2012
  • On the basis of the potentials for the growth of local economy and the result of investigation of the ocean space development status, an ocean resort complex was proposed at the small harbor with a parallel beach in the east coast of Korea. As the development plan needs to reclaim the noticeable amount of coastal water area together with the applied shore facilities, it is necessary to analyze their impacts. Here, it was intended to analyze the coastal environment change such as water circulation and bottom change because of the development plan. A horizontal two-dimensional numerical model was applied to represent the combined impact of wind waves and tidal currents to sediment transport in that coastal region. Based on the result of 30 days tidal current simulations considering major four tidal components of $M_2$,$S_2$,$K_1$ and $O_1$ for the upper and lower boundaries and wind field data, bottom change was discussed. Flow velocities were not changed much at outer breakwater of Yangpo harbor. Bottom was eroded by maximum 1.7m after construction but some locations such as lee side of outer breakwater and some islets near the entrance shows isolated accretions. Although it needs more field observations for bottom change in the period of construction, the numerical calculation shows that there exist small impacts near the entrance area and coastal boundaries because of the development.