• Journal of Korean Society of Coastal and Ocean Engineers
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• v.16 no.2
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• pp.75-82
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• 2004

The changes of sea bottom configuration, which may cause the coastal disasters, have been considered as social problems. It is obvious that the beach deformation is attributable to the sediment transport associated with erosion and acceration. The prediction method and countermeasures for them, however, are not on the level of satisfaction, which indicates that efforts should be made on developing them. In this study, it is found at the groin constructed in Sangju beach on e purpose of beach protection did the aversive function. The reason for this was judged that they accelerated the speed of erosion by increasing the velocity wave-induced current rather than brought storage effect of sediment. Authors found that the storage sediment estimation model by Sonu and Beek(1971) is a useful model at the Sangju beach with the use of topographical survey data from July, 1987 to March, 2003.

• Ocean and Polar Research
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• v.28 no.2
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• pp.209-214
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• 2006

The East Sea Branch (ESB) of KORDI will be launched in 2008. She will take a role of monitoring the sea surface topography and temperature by satellites, short- and long-term sea levels by tide gauges, coastal currents and open-sea circulation by setting up coastal radars and mooring current-meters and acoustic equipments, as well as monitoring nearshore processes, coastal erosion and water pollution. A basic program of coastal zone management will help ocean-policy makers to set up right decisions based upon scientific background of the regional data in the East Sea. Networking among the neighboring countries around the sea will supply more useful information not only for experts but also for ordinary vacationers or fishermen. In order for this program to be successfully settled down during the next decade, it is necessary for a leader to have the right vision to attract more experts from global brain pools and to manage the ESB as a leading-edge observatory in the world. Details about this leading-edge operational program are introduced in the text.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2003.08a
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• pp.227-232
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• 2003

연안침식현상은 우리나라 핀 해역에서 다양한 원인에 의해 발생하고 있으며 침식현상에 따른 해안선후퇴, 백사장상실. 기타 해안재해의 배후지 전파증가 등 다양한 피해가 발생하고 있다 연안침식현상에 대한 연구는 다양하게 이루어지고 없으나 대부분 개별지역의 침식현상규명 및 대책을 위한 연구가 대부분이며 우리나라에서 발생하는 다양한 침식현상에 대한 전체적인 개관이 이루어지고 있지 못한 것이 현실이다. (중략)

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.5
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• pp.691-699
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• 2021

The global surface temperature has risen critically over the past century and according to the IPCC Fifth Assessment Report 2014, existing risks in natural and human systems will worsen. Coastal erosion is mostly caused by climate change and among all the coastal areas at risk, Benin, which is part of the Gulf of Guinea, has been ranked very highly as a vulnerable region. Therefore, in this review, we focus on the evolution of coastline change in Cotonou of Benin, summarizing its resultant impacts and applied measures around the coast area by reviewing previous studies. Signs of coastal erosion in Cotonou appeared in 1963. After 39 years, the east shoreline of Cotonou has retreated by 885 m, resulting in the disappearance of more than 800 houses. To solve this problem, Benin authorities built seven groynes in 2013, and have increased the number of the structure as a way to interrupt water flow and limit the movement of sediment. Over the region, shorelines appeared preserved accordingly. In contrast, areas located further east, where groynes were not installed, have suf ered from intensive erosion at a rate of 49 m/yr. In the future, as a next step, the effectiveness of groynes should be studied with local and broader perspectives.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.27 no.2
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• pp.105-112
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• 2015

In this study, the erosional properties of deposit bed for the natural sediments are quantitatively estimated domestically for the first time using annular flume. Four erosion tests for Saemankeum sediments have been carried out on different consolidation time. Experimental results of erosional tests show that shear strength ${\tau}_s$ increases with the increases of consolidation time and bed depth. The erosion rate increases logarithmically with the increases of exceed shear strength ${\tau}_b-{\tau}_s$. But, the erosion rate decreases rapidly with the decreases of exceed shear strength under the $0.2N/m^2$. Experimental results of this study are found to be remarkably different in quantity as compared with those for results of previous study.

• 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.

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.264-264
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• 2017

• Journal of Forest and Environmental Science
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• v.31 no.3
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• pp.225-234
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• 2015

Mangroves are important coastal ecosystems and are located at the inter-tidal zones of tropical and sub-tropical belts. The global mangrove forests are declining dramatically because of the conversion of forests to shrimp farming, over-exploitation, pollution and freshwater diversion. The Bangladesh Forest Department initiated mangrove afforestation throughout the coastal belts of Bangladesh in 1966 to provide better protection for the coastal communities. Up to 1990, 120,000 ha of mangroves had been planted and it is one of the largest coastal afforestaton programs in the world. The objective of this study is to exploit the spatial extent of mangrove plantation and their dynamics of changes over the last two decades using multispectral Landsat imagery. The study area covers the coastal areas of Bangladesh that is extended over the eastern part of Sundarbans up to Teknaf, the southern tip of mainland Bangladesh. Mangrove plantations were interpreted visually on computer screen and interactive delineation of forest boundary was done. The mangrove plantation area has been estimated as 32,725, 47,636 and 43,166 ha for the year of 1989, 2000 and 2010, respectively. Mangrove deforestation by human activity has increased almost six times in the recent decade in comparison to the previous one. The mangrove forest loss due to coastal erosion has slightly declined in the 2000s. Mangroves have been lost primarily because of agricultural expansion. The result of this investigation will be helpful to understand the dynamics of mangrove plantation and the main drivers of changes in this coastal ecosystem.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.16 no.4
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• pp.258-267
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• 2004

Coastal and harbor structures, which are constructed for the beach protection and coastal zone development, often cause the severe beach erosion problem resulted from changes of longshore sediment transport. In this study, we present a new methodology to estimate the longshore sediment transport rates using the measured data of beach profiles or shorelines. The methods is applied for the prediction of longshore sediment transport rates along Kailua beach, Hawaii and shorelines in the vicinity of Anmok Harbor, Korea.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.767-770
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• 2008

This study was to investigate the establish situation of coastal disaster prevention forest for future-oriented management and establishment method of stands. As a result, the area of coastal disaster prevention forest was about 1,479ha in Korea. Therefore, it is necessary to prepare the thining regime for area of coastal disaster prevention forest and make a management method for fallen poor disaster prevention function of coastal forests. In addition, more positive counterplan would be necessary to conclude the protection against this disasters because the damage from coastal erosion or pine wilt disease were increased partly in some area.