• Journal of the Korean Society for Marine Environment & Energy
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• v.2 no.1
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• pp.102-112
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• 1999

The purpose of this study is to evaluate the effects of design criteria and environmental conditions of the site of created tidal flats on the structure and function of man-made ecosystem. Seven constructed tidal flats and three natural tidal flats were studied taking the difference in the location (wave height and tidal current), inflow of river water, slope of tidal flat and age after the construction completed into consideration. Parameters studied were physico-chemical and biological characteristics of soils and rate of respiration. The natural tidal flats had higher contents of silt, nitrogen and organic matter compared with the constructed ones. The natural ones had reductive zone below 2cm, whereas the constructed ones had aerobic zone from the surface to below 20cm. The bacterial population in the soil of the constructed tidal flats was one to two orders of magnitude lower than that in the natural ones. Both biomass of macrobenthos and microbial respiration rate, however, were not different significantly between the natural and the constructed tidal flats. There was an exceptional constructed tidal flat with similar physico-chemical and biological characteristics to the natural ones. It is most probable that sufficient conditions to have similar tidal flats to natural ones are the location in enclosed bay or calm coastal area. Thus, to make man-made tidal flats with the same characteristics as those in natural ones, man-made tidal flats should be designed and/or located to enhance the accumulation of silt on tidal flat. It is important to select a place having low water motion for construction of tidal flat.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.734-738
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• 2002

We present spectral characteristics of tidal flat sediments and algal mat that were tested in the Gomso and Saemangum tidal flats, Korea. The objective of this study is to investigate the spectral reflectance and the radar scattering modeling in the tidal flats. Ground truth data obtained in the tidal flats include grain size, soil moisture content and its variation with time, surface roughness, chlorophyll, ground leveling, and field spectral reflectance measurement. The concept of an effective exposed area (EEA) is introduced to accommodate the effect of remnant surface water, and it seriously affects the reflection of short wavelength infrared and microwave. The nin size of 0.0625 mm has been normally used as a critical size of mud and sand discrimination. But we propose here that 0.25 mm is more practical grain size criterion to discriminate by remote sensing. Algal mat is the primary product in tidal flats, and it is found to be very important to understand spectral characteristics for tidal flat remote sensing. We have also conducted radar scattering modeling, and showed L-band HV-polarization would be the most effective combination.

• ALGAE
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• v.24 no.3
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• pp.149-161
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• 2009

Characteristics of benthic microalgae and sediment properties were investigated for the intertidal flats of Kwangyang Bay, Korea. Sampling stations were selected every 100 m in the intertidal flats from land-side to open ocean at two different sampling sites. Samples were collected in June 2004, July, September, November, February and May 2005. Sediments properties were measured including temperature, water contents, sediment bulk density, nutrient concentrations in porewater. Chlorophyll a concentrations in surface sediment (0.5 cm) were measured and relationships between the chlorophyll a and various sediment properties were analyzed to identify major mechanisms regulating biomass of benthic microalgae in the intertidal flats using simple linear regression analysis. Sediment chlorophyll a concentrations were maximum during winter and minimum during warm seasons ranging from 4.4 mg $m^{-2}\;to\;81.2\;mg\;m^{-2}$. No clear spatial variations were observed for the sediment chlorophyll a in the study sites. Results from regression analysis suggested that benthic microalgae biomass was affected by sediment temperature and nutrients especially ammonium and silicate. Grazing effect was estimated using chlorophyll: pheopigments ratio, indirect indicator of grazing activity, and the positive correlation of the ratio and chlorophyll a implied that microalgae biomass is affected by grazing of zoobenthos although direct measurement of grazing activity is required to determine the importance of top-down controls in the benthic microalgae dynamics.

• Korean Journal of Remote Sensing
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• v.27 no.3
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• pp.225-234
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• 2011

This study proposes an inversion algorithm to extract the surface parameters, such as surface roughness and soil moisture contents, using multi-frequency SAR data. The study areas include the tidal flats of Jebu Island and the reclaimed lands of Hwaong district on the western coasts of the Korean peninsula. SAR data of three frequencies were accordingly calibrated to provide precise backscattering coefficients through absolute radiometric calibration. The root mean square (RMS) height and the correlation length, which can describe the surface roughness, were extracted from the backscattering coefficients using the inversion of the Integral Equation Method (IEM). The IEM model was appropriately modified to accommodate the environmental conditions of tidal flats. Volumetric soil moisture was also simultaneously extracted from the dielectric constant using the empirical model, which define the relations between volumetric soil moistures and dielectric constants. The results obtained from the proposed algorithm were verified with the in-situ measurements, and we confirmed that multi-frequency SAR observations combined with the surface scattering model for tidal flats can be used to quantitatively retrieve the geophysical surface parameters in tidal flats.

• Journal of Environmental Science International
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• v.17 no.12
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• pp.1391-1402
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• 2008

Designating conservation sites is needed for the preservation and management of tidal flats, and also objective criteria, by which preservation values of tidal flats can be evaluated, are required to designate conservation sites. A set of new evaluation criteria or tidal flats was suggested in this study. The criteria, based on six items including scarcity, diversity, naturalness, uniqueness, destruction possibility and preservation will, ave the advantages with which easy and economic assessments are possible by using basic data from the preceding studies. The evaluation results for the three different tidal lats (Muan, Jeungdo-1 and Jeungdo-2) in the southwestern coast of Korea reveal that all he tidal flats evaluated are classified into grade 2. The tidal flat which got the highest valuation score was Jeungdo-1 tidal flat (86.7), and the next was Muan (85.0) and Jeungdo-2 (82.5). The Jeungdo-2 tidal flat was superior in uniqueness and destruction possibility, and the Muan tidal flat was superior in diversity and naturalness.

• Journal of the Korean Statistical Society
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• v.10
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• pp.122-127
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• 1981

A parallel flats fraction for the $3^n$ factorial is symbolically written as $At=C=(C_1 C_2 \cdots C_f)$ where C is a rxf matrix and A is rxn matrix with rank r. It is shown that the set of all possible parallel flats fraction C for a given A and given size can be partitioned into equivalence classes. The number of those classes are enumerated in general.

• Journal of the Korean Statistical Society
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• v.12 no.2
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• pp.61-68
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• 1983

A parallel flats fraction for the $3^n$ factorial experiment is defined as the union of flats, ${t$\mid$At=C_i(mod 3)}, i=1,2,\cdot,f$, in EG(n,3) and is symbolically written as At=C where A is of rank r. The A matrix partitions the effects into u+1 alias sets where $u=(3^{n-r}-1)/2$. For each alias set the f flats produce an alias component permutation matrix (ACPM) with elements from $S_3$. In this paper, a detection vector of the ACPM was constructed for each combination of k or fewer two-factor interactions. Also the relationship between the detection vectors has been shown.

• Ocean and Polar Research
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• v.24 no.1
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• pp.79-86
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• 2002

It was found that 14 coastal habitats in South Korea have comparetively natural vegetation. The habitats were classified into three types - intertidal flats, sand dunes, and estuaries. There were four intertidal flats, five sand dunes and five estuaries. Except for Cynodon dactylon and Tetragonia tetragonoides, all of the main halophytes and sand dune plants were found in the habitats. These two species were mainly distributed on the southern coast. This study identified coastal vegetation, such as pure stands of Suaeda japonica on intertidal flats, mixed halophyte communities around the high-water mark, pure stands of Vitex rotundifolia on stable sand dunes, mixed communities dominated by Carex kobomugi on unstable sand dunes, and pure stands of Phragmites communis in estuaries. The types of coastal vegetation may depend on sediment types, the inundation time of seawater and the stability of sediments.

• Journal of Environmental Science International
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• v.12 no.7
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• pp.715-724
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• 2003

Distributional patterns of microalgae were studied in the tidal flats of Gamami Beach(Young-Gwang, Korea) from November 1999 to 2000 July. The tidal flats of Gamami Beach was composed mainly of sandy sediment. The concentrations of nutrients were low compared with other tidal flats. In the present study, 68 species of microalgal flora were identified. These were comprised of 25 species of benthic microalgae and 59 species of planktonic microalgae. Diatoms predominated the benthic microalgae with 96.0% of total species occurred. Dominant species were Amphora sp., Cocconeis sp., Coscinodiscus asteromphalus, Coscinodiscus sp., Nitzschia sigma var. intermedia, Nitzschia distans, Navicula spp., Paralia sulcata, Pleurosigma sp. Skeletonema coastatum, and Surirella sp. Among them, Amphora sp., Paralia sulcata, and species of Pleurosigma and Nitzschia were observed throughout the studied period. Planktonic microalgae of Gamami Beach was also predominated by diatoms. They occupied 88.1% of total planktonic microalgae. The density of microalgal population was higher in silty sediment than in sandy sediment. The population density of microalgae was higher in high tide zone than that in low tide zone. The density of the benthic microalgae in the surface layer of tidal flats showed increasing tendency for 2 hours after the beginning of ebb tide. On the contrary, benthic microalgal density of subsurface layer was decreased during the period. Concentrations of chlorophyll ${\alpha}$ from sediment and water were not synchronized during the study period. Therefore, the distributional patterns of the benthic microalgae and planktonic algae seemed not to be related. Chlorophyll ${\alpha}$ of water was highly related with the concentration of NH$_4$-N, whereas, chlorophyll ${\alpha}$ of sediment uas related with NO$_3$-N concentration.

• KIEAE Journal
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• v.14 no.2
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• pp.61-68
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• 2014

This study aims at proposing a sound and sustainable development direction of an residential environment by analyzing testimonies of residents who lived in Park Hill flats or their surround at Sheffield City in the United Kingdom. The results are obtained through the analysis on a residential environment of Park Hill flats, opinions of the residents on its refurbishment, and effects of the building on the residential environment. The block of Park Hill flats was a community with a strong unity and solidarity, but that became increasingly a slum by the decline of the physical and social environment since the 1980s. In particular, it was identified that the deterioration of the social environment than that of the physical environment was a major cause of the decline. Nevertheless, it was found that "streets in the sky", the concept applied in Park Hill, played a key role in activating the community in the apartment complex. However, that street system in the complex has caused noise, poor security, and invasion of privacy. If such problems are solved, the streets in the sky will be a meaningful alternative for community activation and then ensuring sustainability in Korean residential environments that lost the function of the community.