• Korean Journal of Environment and Ecology
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• v.16 no.1
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• pp.34-45
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• 2002

Of the four tidal flat areas(Yeocha-ri, Dongmak-ri, Sundu-ri and Donggum-ri) on Southern Ganghwa Island, the distribution of migratory waterbirds showed a difference in the numbers of individuals and species. Higher numbers of individuals and species were observed on the Yeocha-ri tidal flat. The dominant waterbirds species at the four areas was the Dentin(Calidris alpina). This species showed an occupancy rate(42.0-79.1%) on the Yeocha-ri tidal flat, which was much higher relative to the other areas. The Yeocha-ri tidal flats were higher relative to MSL than the other tidal flats. When the Dongmak-ri tidal flat was covered by sea water, the Yeocha-ri tidal flat was 0.0317$\textrm{km}^2$ in area and on this space we observed many resting waterbirds. The biomass of the waterbirds' potential prey on the Yeocha-ri tidal flat was higher(1.6~2.5$\times$) than other tidal flats. Twenty-three species and 266 individuals were found on the Yeocha-ri tidal flat, which was higher than the tidal flats. The food of Dunlin, which was the dominant species in these four areas, was mainly Reticunassa festiva and Umbonium thomasi(Gastropoda) and Perinereis aibuitensis(Polychaeta). A Dunlin(38.11g) used to eat 1,295 individuals of these food items for daily basal energy. Gastropod, its density was highest on Yeocha-ri tidal flats. The distribution of waterbirds seemed to be closely related with the distribution of the benthos, space and safety of resting site. We suggest that the environments of tidal flats, which are rich foraging habitats, are important factors for conservation of waterbirds.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.15 no.2
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• pp.127-137
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• 2003

The researches on the construction of artificial coastal wetlands have been progressed in order to cope with the situation that the area of Korean tidal flat has been reduced due to several coastal developments This study, as a part of the project on construction of the artificial tidal flats, deals with the comparison of the geotechnical characteristics between natural tidal flat and artificial tidal flat, and is also focused on the stability analysis of tidal flats. Various laboratory tests were performed using disturbed and undisturbed samples, which were obtained from a sandy tidal flat in Korea. The stability of the sandy soils accumulated on the tidal flat was investigated by comparing the shear strength of soil evaluated from laboratory test with induced shear stress due to both current and wave action.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.3
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• pp.110-121
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• 2021

The importance of tidal flats lost due to industrialization has recently received attention, and attention is being paid to the creation of artificial tidal flats and maintenance of natural tidal flats. However, there is still a lack of understanding about the behavioral characteristics of mud, mud, and sand that form tidal flats. Although research on the movement characteristics of mixed soils such as tidal flats has been conducted through field investigations and hydraulic experiments, interest in developing a numerical model based on these results has not yet reached. In this paper, the purpose of this paper is to establish a mixed soil model that can efficiently manage the low quality of the tidal flats. In constructing a model for reproducing the surface movement of mixed soil, the numerical stability of the reproduction and movement of sand and mud constituting the mixed soil in the numerical model should be considered first, so first, the volume of sand and mud constituting the mixed soil A mixed soil model representing the relationship was proposed based on a topographical diagram representing the geometric structure of the mixed soil. In order to consider the dry bulk density of the mixed soil, it was possible to consider the dry bulk density of the mud by introducing the water content of the mud containing water. In addition, it was confirmed that the mud and sand movement calculation according to the slope collapse of the mixed soil was stably performed through the calculation of the slope collapse of the mixed soil through the numerical analysis model to which the proposed mixed soil model was applied.

• Korean Journal of Remote Sensing
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• v.5 no.1
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• pp.1-12
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• 1989

The objective of this study is to develop the application techniques, such as geometrical correction, image overlapping etc., of LANDSAT Thematic Mapper image data especially useful to the geomorphological study of tidal flats. The developed processing techniques were applied to the Kum river estuary. The results of this study are as follows. 1) According to the analysis of the distribution and topographical profiles of the tidal flats, the geomorphological characteristics of the study area seem to be different depending on their location. 2) Even though the geomorphological changes were not always observable on the satellite images, several areas of undoubtful short-term deposition could be detected on the analytical map-image which compares two different situations of tidal flats. 3) Even though a further ditailed study is necessary, the distribution and dispersal patterns of suspended materials and sea surface temperature distribution patterns due to tidal and other meteorological conditions were analyzed by LANDSAT TM channel 3 and 6.

• Journal of The Geomorphological Association of Korea
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• v.24 no.1
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• pp.105-116
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• 2017

This article is written in the viewpoint of landscape ecological geography. The coast of South Chung-chong Province will make new characters of region in the development strategies program. This study is to describe geomorphological landscapes of South Chung-chong Province relating with it's environment based on the coast. Although landforms constitute prominent landscape features as tidal flats and rock cliff do, it is nonetheless the features such as beaches, sanddunes, and coastal plains that have various ramifications for human communities. Tidal flats, beaches and coastal sanddunes are special in that their formation is attributable to the combined action of tidal flows, waves and winds. To some extent, the erosion of sand has been a global phenomenon. Human impact are involved. The influence of globalization and expansion of liberal trade appears in regions variously. Individual regions need to secure its competitiveness in the world market. Regions are not value-neutral abstract conception, but must be informal commercialized characters of region. The coast of South Chung-chong Province has experienced rapid and dramatic changes. In industrial times, the middle of west coast Korea turned into a major reclamation at larger scale. Reclaimed land was based on location of industry and mechanized agriculture. The west coast highway and bridges between island and land contributed to the development of west coast transportation. As information society matured, trend and value are changing. Environment and ecology emphasize and rediscover the value of tidal flats and sanddunes. The west coast region now receives attention as eco-tour and sustainable course.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.14 no.2
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• pp.151-160
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• 2002

A modeling system for three-dimensional flow (FEMOS) has been developed and applied to simulate the tidal currents of Asan Bay. The system can consider tidal flats changing with time and uses a finite element method that can adapt coastline change effectively. The simulation results for Asan Bay with large tidal flats, shallow water depth and high tidal range showed good agreements with the observed currents of long-term variations at the medium layer and short-term variations of vertical profiles. Based on the simulated tidal currents, the horizontal distributions of bottom shear stress were calculated and showed close relation with the change of bottom topography. The system can be used widely to study coastal circulation in the coastal region with complex geography.

• ALGAE
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• v.33 no.2
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• pp.167-180
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• 2018

Benthic diatoms are ubiquitous in tidal flats and play major roles in maintaining coastal ecosystems. Spatio-temporal variations in diatom diversity have not been well-studied, mainly because of difficulties in morphological identification and the lack of appropriate genetic tools. To overcome these problems, we used the gene encoding the ribulose bisphosphate carboxylase large-subunit (rbcL) as a molecular marker, and sequenced these genes with the aid of the MiSeq platform. In this manner, we explored the genetic diversity of benthic diatoms in tidal flats of Guenso Bay on the west coast of Korea; differences in the spatial distributions of benthic diatoms were evident. The diatom communities were dominated by Nitzschia, Navicula, and Amphora; their relative distributions were affected by the sand proportion, grain size, and air exposure time. Our results suggest that meta-barcoding of the rbcL gene and next-generation sequencing can be used to explore the diversity of benthic diatoms.

• Ocean and Polar Research
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• v.25 no.4
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• pp.593-601
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• 2003

The purpose of this paper is to investigate economic feasibility of creating artificial tidal flats using cost-benefit analyses. We assumed that the cost factors are associated with designing, construction and monitoring, and the benefit factors are associated with fisheries production, habitation, prevention of disasters, water purification, aesthetic value and existence value. First, for analyzing economic feasibility, the scenario suggests that a design can be made in a year, construction can be completed in three years and monitoring must be made for 20 years. Assuming the discount rate of 7.5%, economic feasibility analyses showed that B/C was 2.26 and IRR was 14.50. This study indicated there is economic validity of implementing creation of artificial tidal flat. In addition, we carried out a sensitivity analysis at the change of discount rate and restoration rate. The result of sensitivity analysis clearly showed that economic validity is low when discount rate is over 15%, and changes in restoration rate did not significantly effect on the economic validity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.4
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• pp.409-415
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• 1999

To evaluate the purification capacity of pollutants (COD, $PO_4^{3-}-p$, $NO_3^{-}-N$, Cu, Cd, Pb) in the three tidal flats, Eueunri, Gyewhado, Chunjangdae, the experiments were carried out with the batch reactor equipped with artifical tidal flats. Eueunri tidal flat was $98.8\%$ content of silt and clay and Chungjangdae was $97.84\%$ content of sand. The organic matters (I.L., $COD_{sed}$, POC) in Eueunri tidal flat were 2$\~$8 times higher than other tidal flats. The purification capacity of COD was 0.75 kg/ha/12 hr in Eueunri, 0.60 kg/ha/12 hr in Gyewhado and 0.55 kg/ha/12 hr in Chunjangdae. The mean purification capacity of COD in three tidal flats was 1.27 kg/ha/day. The calculated purification capacity of COD was 25.4 ton/day in the disappeared tidal flat areas (20,000 ha) of the Saemangeum reclamation. The purification capacity of phosphorus was 0.21 kg/ha/12 hr in Gyewhado, 0.39 kg/ha/12 hr in Eueunri and 0.22 kg/ha/12hr in Chunjangdae. The nitrate was 0.53, 0.74 and 0.43kg/ha/12hr, respectively. The purification capacity of heavy metals (Cu, Cd, Pb) were 88.9g/ha/12hr, 11.0g/ha/12hr, 1.7g/ha/12hr in Gyewhado, 89.1g/ha/12hr, 18.0g/ha/12hr, 2.6g/ha/12hr in Eueunri and 55.3g/ha/12hr, 18.0g/ha/12hr, 2.1g/ha/12hr in Chunjangdae, respectively. Accordingly, the purification capacity of pollutants in Eueunri tidal flat with high contents of organic matter were higher than other tidal flats. So, the purification capacity of pollutants were affected by physical and/or chemical characteristics of tidal flats.

• KCID journal
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• v.5 no.2
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• pp.41-51
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• 1998

Spatial distributional patterns of temperature in the sediments and the concentration of nutrients in interstitial water were particular interests on the ecological research of tidal flats. It was the aim of this paper to grasp inhabiting environment of t