• Journal of Environmental Impact Assessment
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• v.11 no.4
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• pp.247-258
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• 2002

This study aimed at verifying the grain-sized distribution of surface deposits in a tidal flat using multi-spectral Landsat TM. In this study, we employed the grain-sized analysis, PCA and unsupervised classification techniques for analyzing the distribution of deposits. As a result in this study, the unsupervised classification method using PCA image was found to be most useful in classifying tidal flat deposits using satellite data. This method is considerably effective in analyzing not only the aspects of distribution in terms of accumulated deposits and erosion, but also the changes in seaside topography and shoreline. The grain-sized distribution analysis indicates that the mud flat inside the Cheonsu-bay tidal flat is distributed, the mixed flat located in the middle, and the sand flat distributed near the sea. The sand flat is dominant around the southern part of Seomot isle and its beach. On the other hand, the mud and mixed flat is dominant on the western part. Likewise, the western coast of Seomot isle and its beach is significantly affected by waves facing the offshore. However, the eastern side of the bay could be a site for the evolution of tidal flat made of fine materials where it is less affected by ocean waves. These results show that multi-spectral satellite data are effective for the classification of distribution materials and environmental impact assessment and continuous monitoring. In particular, the research on environmental deposits can provide important decision-supporting information for decision-making on seaside development, by analyzing the progress of deposits and environmental changes.

• Korean journal of food and cookery science
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• v.13 no.5
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• pp.585-591
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• 1997

The proximate composition and physicochemical properties of three cultivars of Korean kidney bean sediments, Pink (PKB), Red (RKD) and White (WKB) were compared. No significant differences in the proximate composition and calorie were noticed among three samples. Sediment granule was oval/round and rough in all samples. The amylograms showed no peak and continuous increase of viscosity during heating. The water-binding capacities of the sediments were 322.4∼355.0%. The swelling power and solubility were 5.93∼6.68% and 3.76∼5.28%, respectively. The percent transmittances of the sediment suspension decreased linearly from 50$^{\circ}$∼75$^{\circ}C$. The gelatinization temperature and gelatinization enthalpy determined by DSC (Differential Scanning Caloriemeter) were much lower than those of starches.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.9
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• pp.597-603
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• 2012

To investigate the effects of weir construction on sediment characteristics of river bed, we conducted sediments sampling on the 9 locations near the weir, Kangchun, Yuju and Ipo in Namhan-River. Physical and chemical characteristics of sediments were analyzed by measuring particle size distribution, water content, Ignition loss, COD (Chemical Oxyzen Demand), TOC (Total Organic Carbon), TP (Total Phosphorus), SRP (Soluble Reactive Phosphorus) and TN (Total Nitrogen). Particle classification of all three weir sediments showed sandy loam that was caused by the river bed dredging. Due to the presence of weir, Ignition loss, COD, TOC, TP, SRP and TN showed similar trend such as the concentrations of upward weir had higher than those of downward weir. For the case of SRP concentration and C/N ratio, however, there is not much difference in the sediment characteristics compared to the those of sediments before weir construction. Therefore, It can be predicted that there are little effects of weir construction on sediment characteristics. However, weir construction could influence water quality of the river by controlling the transport and the accumulation of suspended materials from rainfall. Therefore, more intensive monitoring is required to examine the magnitude and patterns of sediment accumulation which could influence overlying water quality.

• Journal of The Geomorphological Association of Korea
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• v.18 no.3
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• pp.37-51
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• 2011

Geomorphic changes and sedimentary changes are investigated by sediment analysis from estuarine tidal flat, Mosan Bay Estuary, which is a tide-dominated and rias estuary. Sediments separatedly deposited during the early Holocene and the late Holocene. There are unconformities between the early Holocene sediment unit and the late Holocene sediment unit. Developments of these unconformities were related with fluctuated sea level change during the mid Holocene. Three deposit zones are spatially classified, which are named "intermittent tide channel deposit zone"(A1, B1, D3), "flood-dominated deposit zone"(A3, B3, C1, C3), and "fluvial sediment deposit zone"(A2, B2). This classification is explained by three main effects; laterally restricted migration of a tidal channel, diffract flood effect and settling lag effect, and fluvial induced reworking. These effects are deserved as main factors which have formed estuarine geomorphology in tidedominated and rias estuary. This study suggests research directions in reconstructing estuarine geomorphic and sedimentary change in west coast of Korea. Furthermore, it gives useful data for making a "land-ocean interaction" model for west coast of Korea.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.2
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• pp.101-110
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• 2013

In order to classify the trophic state and environmental quality of marine coastal system, an approach using the characteristics and biochemical composition in the sediments can be available. This research, including 25 coastal bay, belong to 131 stations, was carried out along the south coasts of Korea in February 2007. Type of sediment, total ogranic carbon, total nitrogen, phytopigments and biochemical composition(proteins, lipids, carbohydrates) were analyzed. Result from Multi-dimensional Scaling(MDS) ordination indicates that four group can be identified. The result of ANOVA with tukey test shows that the concentrations of proteins, carbohydrates and biopolymeric carbon were significantly different to four groups. We propose the trophic state classification for these groups using the biochemical composition of sediment organic matter. I group(Masan, Jinhae, Haengam) has been defined as hypertrophic state, II group(Tongyeong, Goseong；Jaran, Geoje et al.), as eutrophic; III group(Gamak, Deungnyang, Yeoja et al.), as mesotrophic and IV group(Sinan, Jindo, Muan), as oligotrophic. On the basis of results reported in this study, the biochemical composition of sediment organic matter could be considered an useful and sensitive tool for the classification of the trophic state of marine coastal systems.

• Journal of Korea Water Resources Association
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• v.42 no.2
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• pp.141-148
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• 2009

Each river in each country has peculiar channel characteristics at every section. Korea consists of mountains at the rate of 70%. Due to this, the sections that display unique channel form are scattered. One of the typical features is the narrow pass of channel section that presents in the process of the generation of alluvial channel and deformation channel. Around as this narrow pass of channel, it often comes to be regular flood disaster section. Regardless of this situation, investigations and plans that reflect channel characteristics at the narrow pass of channel have been wholly wanting until now. In accordance with this, we have investigated and analysed hydraulic significance and channel form of the narrow pass of channel in Seonsan in this study. The study has found real minute classification of sediment phenomenon at river bed of low flow channel on investigation section which is sand-bed river, but it was vaguely difficult to conclude that classification of sediment arises from explicit natural force. We were able to assume that the phenomenon comes from gentle bed slope, supply of river bed materials which is nearly uniformity. However, classification of sediment would come from collecting an aggregate rather than natural force. And we found that compound cross section conversion has been developing dramatically with channel form of movable bed section referring to movement which was active before at drainage district of the narrow pass of channel. With this, we could find the phenomenon that river width of low flow channel diminished largely. This kind of situation implies that it may cause compound section weighting, flood dimension decreasing, revetment at low flow channel or the local scour at bottom of levee when extraordinary flood occurs.

• Journal of the Korean Geographical Society
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• v.49 no.2
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• pp.221-244
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• 2014

We suggested several implications by examining geochemical properties of sediments in Simjeok, Jangdo, and Hwaeomneup mountain wetlands which are natural preservation areas. Geochemical properties of wetland sediments show that all wetlands were included in the type of fens, but their distribution patterns were different from one another. We classified three sub-groups of sediments using the two step cluster analysis on the ratio of exchangeable cations. Wetland sediments can be grouped into Ca-dominated, Mg-dominated, and K-dominated types. Simjeok wetland have Ca-dominated sediments, while the sediments of Jangdo wetland indicate the Mg-dominated and Ca-dominated characteristics. Hwaeomneup wetland is composed of K-dominated sediment mainly. Different properties in the ratio are affected by various environmental factors such as geological, pedological, and vegetational settings. Because these geochemical properties will be affected by climate change and human impacts, these will be environmental indicator in mountain wetlands and be used in wetland management. This scheme can be used for classification of mountain wetlands. Therefore, we should work on geochemical properties of wetland sediments and classification schemes based on geochemical properties not only to widen understanding in geomorphic system or ecosystem of mountain wetlands but to conserve mountain wetlands properly.

• Water Engineering Research
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• v.2 no.4
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• pp.269-276
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• 2001

The project concentrates on an hydrological analysis. The analysis consists of rainfall, infiltration, Determination of runoff and sediment yield. The risque of erosion and the control measures are related to the slopes and land use. Therefore the first approach to erosion must be correct land use based on land classification. Basically there are two types of mechanical protection works; Drainage and Storage. Realization of a drainage system will be very costly and therefore temporary storage is preferred. For farmland in flat areas hardly any measures are needed. For farmland on slopes temporary storage can be effected by applying tillage with ridges within contour bunds. Along roads infiltration pits should be constructed and in areas with houses, the solution to avoid runoff will be water harvesting.

• Journal of Ecology and Environment
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• v.34 no.4
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• pp.333-345
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• 2011

Aquatic macrophytes, often also called hydrophytes, are key components of aquatic and wetland ecosystems. This review is to briefly summarizes various macrophyte classifications, and covers numerous aspects of macrophytes' role in wetland ecosystems, namely in nutrient cycling. The most widely accepted macrophyte classification differentiates between freely floating macrophytes and those attached to the substrate, with the attached, or rooted macrophytes further divided into three categories: floating-leaved, submerged and emergent. Biogeochemical processes in the water column and sediments are to a large extent influenced by the type of macrophytes. Macrophytes vary in their biomass production, capability to recycle nutrients, and impacts on the rhizosphere by release of oxygen and organic carbon, as well as their capability to serve as a conduit for methane. With increasing eutrophication, the species diversity of wetland macrophytes generally declines, and the speciose communities are being replaced by monoculture-forming strong competitors. A similar situation often happens with invasive species. The roles of macrophytes and sediment microorganisms in wetland ecosystems are closely connected and should be studied simultaneously rather than in isolation.

• Ocean and Polar Research
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• v.35 no.1
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• pp.27-37
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• 2013

The western coast of Anmyeondo is open toward the Yellow sea and the northern and southern coasts are sandy and have simple coastlines. In this study, we investigated the spatial distribution and community structure of the macrobenthos that inhabit the sandy shore of Anmyeondo. For the study, we chose 8 sites encompassing 44 stations. In total, we have recorded 62 species, and collected 747 inds./$m^2$ on average. Zonation pattern did not appear because the mean grain size and organic contents of the study sites were similar among the macrobenthos. Polychaetes were most frequently recorded, but amphipods appeared in higher mean density. Macrobenthic community is classified into 3 groups largely based on the density difference among the dominant species and the groups were not influenced by environmental factors. The aggregated distribution of macrobenthos did not show a clear regional spatial difference but exhibited classification pattern emphasizing the density difference of the dominant species. The sandy shores of Anmyeondo are relatively more influenced by waves compared to other regions and the sediment moves more due to strong winds, etc. at low tide. We presume that the movement of sediment resulted in a relatively even sedimentary environment and consequently weakened environmental variables that change with the tide level. We concluded that the macrobenthic community does not show the zonation pattern in the sandy shores of Anmyeondo due to such influences.