• 한국해양학회지:바다
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• 제2권2호
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• pp.87-91
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• 1997

시화 방조제의 건설로 형성된 시화 인공호수의 생태적 안정성을 동물플랑크톤의 종 조성과 생물량 변동을 통해 파악하였다. 방조제 바깥쪽 해수면의 동물플랑크톤은 인근 아산만의 경우와 매우 유사한 종 조성과 계절간 변동을 보였다. 그러나, 시화호의 동물플랑크톤은 기수종으로 알려진 요각류 Sinocalanus tenellus 단 한종이 차지하는 비율이 절대적으로 높았으며(봄철 약 66%, 겨울철 약 80%, 여름과 가을에는 98% 이상 점유), 종 조성이 매우 단순하였고, 생물량에 있어서도 $10^4$ 단위까지 차이가 나는 매우 격심한 변동을 보였다. 이러한 변동은 인공호수인 시화호가 생태적으로 매우 불안정한 상태에 있음을 보이는 것이며, 그 원인은 담수 유입시의 오염 부하량의 변화나, 부정기적인 수문의 개폐와 수문 개폐시의 물의 흐름 방향의 가변성 등에 기인된 염분의 불규칙적인 변화 등이 주요 원인으로 판단되었다.

• 한국농공학회논문집
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• 제52권3호
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• pp.1-7
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• 2010

The ichthyofauna and passing efficiency of fishways were surveyed in Geumgang estuary from May to October in 2009. The fishes collected were classified into 24 species, 23 genera belonging to 8 families. These 24 species consist of 17 freshwater fish species, 3 migration fish species and 4 peripheral freshwater fish species. Seasonal function of fishways showed the migration from May to June and returning to the reservoir of fishes be washed out to sea when sluice gate open by rainfall in July and August. Most of the fishes catched in fishways moved from middle tide to high tide except for July. Fishes ascended fishways between the middle ebb tide and the ebb tide only July, because small freshwater swim against the fishway for leaching the reservoir through the newly formed flow when the water level at the fishway kept dropping. Small fishes that body length less than 200 mm mainly used gabion type fishways and fishes over 200 mm utilized a cascade type fishways. Based on the total individuals collected, the efficiency of the fishway was 1 % for the anadromous fish and over 80 % for freshwater fish. Therefore, it is concluded that ecological function of the fishway in the Geumgang estuary dike be very important not only for fish migration but also freshwater fishes's returning.

• 한국토양비료학회지
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• 제47권1호
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• pp.16-22
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• 2014

This study was conducted to determine the changes in soil chemical properties and the growth of seedling according to the different dredged soil improving methods at slope of Saemangeum sea dike. Undersea dredged soil was improved by five different methods. Seedlings of Ulmus davidiana var. japonica, Chionanthus retusa, Celtis sinensis, and Pinus thunbergii were planted after 9 month of experience site installation, then soil pH, NaCl concentration in soil, soil organic matter (SOM), and survival rate and height of seedling was measured. Initial soil pH was highest in the control plot but it decreased to the similar level with other soil improving plots after 35 months. There were no differences in NaCl concentration between the control and soil improving plots, and it showed decreasing tendency during the study period. In the control plot, initial SOM was lowest among that of other plots during the study period. The survival rate of 36 months after planting of P. thunbergii was highest among the species. The gap of the tree growth of P. thunbergii between the control plot and the soil improving plots was small, however, other species showed relatively higher tree height in the soil improving plots than the control plots. Creation forest with P. thunbergii might be a cost effective afforestation in coastal reclaimed land since it rarely needs additional improvement of dredged soil.

• 한국환경복원기술학회지
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• 제18권1호
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• pp.13-23
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• 2015

This study was performed to compare the effects of different drainage layers on tree growth at the exposed sites of Saemangeum sea dike. 4 types of drainage layers including control(dredged soil), specially prepared bark, gravel, and wood chip were set in 150~165cm depth of soil. Pinus thunbergii and Celtis sinensis were planted after 9 months of soil treatment. Electrical conductivity(EC) of soil in all treated plots were decreased under $4dS{\cdot}m^{-1}$, and NaCl(%) was decreased under 0.05% after 1 year from soil treatment. Soil moisture at the 120cm depth of the bark treated plot was higher than that of the 180cm soil depth, below the drainage layer. It is considered that vertical mobility of water was inhibited. Organic matter(OM) at the 120cm soil depth increased at bark and wood chip treated plots. Survival rates after 4 years of P. thunbergii and C. sinensis were 100% in all treatments. The height of P. thunbergii was not significantly different among the treatments while the height of C. sinensis was significantly different among the treatments and it was highest at the bark treated plot.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.155-161
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• 1999

The land reclamation area of Saemangeum(Kunsan) is located between 126$^{\circ}$10' E~126$^{\circ}$50' E and 35$^{\circ}$35' N~356$^{\circ}$05'N at the western coast of the Korean peninsula. The are many small islands including extensive areas of semi-diurnally flooded and dewatered tidal flats. The reclamation area of Saemangeum has a range of 5.6m spring tide and the maximum tidal current speed is about 1.41m s-1 in ordinary spring tide. Most of the sediments deposited on the tidal flats are transported from the Geum river, the Manjyung river and The Dongjin river. The soil in this area consists of silty sand with the depth of 10m to 30m . The wind in winter is strong from the direction of northwest. In the past twenty years, land reclamation projects for agricutural purpose or industrial cocmplex have been mostly implemented along the western coast of Korea. Saemangeum coastal area is being constructed the33km sea dike and 40, 100ha reclamation area. The purpose of this study is to find the residual circulations in four seasons after the dike construction by a robust diagnostic and prognostic numerical model. Heat flux at the sea surface in January ,May , August , October was asopted on the basis on the daily inflow of solar radiation at the earth surface, assuming an average atomospheric transmission and no clouds , as a function of latitude and time of year(George L.P.J.E William, 1990). The discharge from the Geum , the Mankyung and the Dongjin rivers was adopted on the basis of experience formula of river flow in January , May ,August, October (The M. of C.Korea, 1993) . Water temperature and salinity along the open boundaries are obtained from the results of field observation s.

• 한국농공학회논문집
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• 제55권6호
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• pp.187-196
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• 2013

This study is focused on analyzing the deformation types of seaside armor stones based of field survey in order to establish the cause of abrasion following the deformation of seaside armor stones. 1. The deformation of seaside armor stone in saemangeum sea dike was classified as three different types: floating, deviation, and abrasion. 2. It was discovered that the stones floated to the extent of maximum 50 m, as the result of inspecting floating stones which were situated on different ten places. 3. The average number of deviation in the high ocean wave section was four times more than that in the ordinary ocean wave section, as a result of comparing the deviation number of the ordinary ocean wave section and that of the high ocean wave section for the purpose of inspecting the relation between the deviation of armor stones and the effects of ocean wave. 4. The angular shape of armor stones seen in the initial construction period has been abraded smoothly, as result of comparing of the shape change of armor stones for the purpose of inspecting abrasion state of seaside armor stones. 5. It was discovered that the abrasion of armor stone was severe in the section of many floating stones, as a result of analyzing the levels of abrasion and the cumulative sections of floating stones for the purpose of investigating the cause of abrasion.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2006년도 학술발표회 논문집
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• pp.574-578
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• 2006

Tidal amplification by construction of the sea-dike and sea-walls had been detected not only near Mokpo Harbor but also at Chungkye Bay which is connected with Mokpo Harbor by a narrow channel. This brings about increase of tidal flat area and in particular increase of surge-wave combined runup during storms. The purpose of this study is to examine an efficient operational model that can be used by civil defense agencies for real-time prediction and fast warnings on wind waves and storm surges. Instead of using commercialized wave models such as WAM, SWAN, the wind waves are simulated by using a new concept of wavelength modulation to enhance broader application of the hyperbolic wave model of the mild-slope equation type. Furthermore, The predicting system is composed of easy and economical tools for inputting depth data of complex bathymetry and enormous tidal flats such as Mokpo coastal zone. The method is applied to Chungkye Bay, and possible inundation features at Mokpo Harbor are analyzed.

• 수산해양교육연구
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• 제29권3호
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• pp.627-635
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• 2017

Sea level rise caused by climate change has become a global issue. Sea level rise seems to be an important factor of the research for coastal areas as it affects topography and vegetation of coasts and especially for the plan of coastal wetlands restoration which needs to be carried out for a long term, it has to be considered sufficiently. The coastal wetlands in Korea was damaged by the land reclamation project but recent concerns on the restoration have increased as its value is evaluated highly. Suncheon Bay had also reclaimed from wetlands to rice field once however this site is very active for restoration nowadays. This study estimated an effect according to sea level rise by 2100, reappearing the none dike condition of Suncheon Bay so that it can be taken account of a future plan of wetland restoration. The Sea Level Affecting Marshes Model(SLAMM) was selected as predicting model. The input data such as DEM(Digital Elevation Model), slope, wetlands category, sea level rise senario, tidal range and accretion rate was applied for the simulation. The results showed a decrease in tidal flat, an increase in sea area and a change of the rice field to transitional salt marsh consistently by 2100. These results of this study could be used as baseline data in the future plan of ecological restoration in Suncheon Bay.

• 한국해안해양공학회지
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• 제18권4호
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• pp.301-307
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• 2006

서해안과 같이 큰 조차를 가진 연안해역에서 항만건설과 매립사업이 널리 진행되고 있으며, 대부분의 사업은 방조제 건설을 필요로 한다. 대부분의 방조제는 내부와 외부사이에 해수가 교환되지 않으나, 사석만을 사용해서 축조된 방파제와 가호안의 투수성 제방에서는 해수가 교환된다. 내부의 수면은 외부 조위의 변화에 따라 시간에 따라 변화하나 그 조차는 해수교환시 제방에서의 큰 마찰로 인하여 외부보다는 작다. 지금까지의 연구에서는 제방을 통한 해수교환을 무시하는 것이 조석모델링에서 일반적이다. 이는 내부의 해수면 변화를 계산할 수 없을 뿐 아니라 물막이 공사와 같이 일부 개방구간이 존재하는 경우에 개방구간만을 통한 해수교환량만을 고려하고, 제체를 통한 해수교환량을 무시하여 내부의 조위와 실제 해수교환량을 부정확하게 계산한다. 본 연구에서는 지하수이론을 이용하여 해수유동모의시 투수성 제체를 통한 해수교환량을 정확히 고려할 수 있도록 하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.29-39
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• 2010

By understanding the construction process of sea dikes and the current state of the thickness and speed of fluid in the bottom layer protection work of final closure gaps, a construction method applicable for the blocking of bottom layer work will be selected. The three construction methods selected will be tested in site through various methods, and the reinforcement of bottom layer protection and impervious effect will be verified. The verification results are as follows: 1) The overall riprap layer were 0.5~1.0m thicker than planned so that the grouting depth and grout input amount increased 2) The applied construction methods permeability of riprap layers were improved from $\alpha{\times}10^{-2}cm/s$ before the construction to $\alpha{\times}10^{-4}cm/s$ after construction. 3) The results of core extraction in order to grossly verify the hardening time and durability allowed the identification of grout injection effect. The amount of filling of the injection was difficult to judge because the slime in many areas made the reading of borehole photography difficult.