• Journal of The Geomorphological Association of Korea
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• v.24 no.2
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• pp.51-64
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• 2017

The paleo-environments including changes in vegetation, climate, and sea level since the middle Holocene(6,400(?)-1,800(?) yr BP) were reconstructed with the special reference to pollen analysis from two trench samples at Yulha-dong, Kimhae-si, southern Korea. The environmental characteristics by the pollen zonation wassummarized asfollows: Pollenzone I(6,400(?)~3,940(?) yr BP)showed the dominance of Quercus species with broad-leaved trees, it was warm condition. Pollenzone II(3,940(?)~2,300(?) yr BP) was characterized to the yellow soil indicating terrestrial environment. Moreover, it showed Alnus-NAP period related to the extension of agriculture and deforestation by the rapid decrease of Quercus and increase of Gramineae. Pollenzone III(2,300(?)~1,800(?) yr BP) showed human impact from the increase of NAP and Pinus. Plenty of Quercus with deciduous broad-leaved trees also suggested warmer condition than before.

• Journal of The Geomorphological Association of Korea
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• v.25 no.1
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• pp.47-65
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• 2018

Frost shattering has traditionally been considered as one of the most effective process in rock weathering. Each slab specimens of five or six rhyolite, basalt and tuff was prepared and put in freeze-thaw cycles and repeated 300 times in the temperature of $-25^{\circ}C$ to $+30^{\circ}C$ and their weathering patterns and products were analyzed by surface observation, particle size, XRD and thin section. As the result, some changes were observed in weathering patterns and weathering products. Rock shattering was more active in waterlogging rather than atmospheric conditions, but there are many differences depending on the type of rock. Rhyolite is hardly weathered by 300 times freeze-thaw cycles and generates the least amount of weathering products. Weathering of Basalt is limited to the surface layer where water can be absorbed, and produces a few amount of platy-shape debris. Tuff are separated by blocky structure which the particles are aggregated along their edges rather than enlarged existing cracks/joins or generated new joints.

• Journal of The Geomorphological Association of Korea
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• v.25 no.1
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• pp.67-80
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• 2018

This study used aerial and terrestrial images to build a three-dimensional model of cliffs located in Pado beach using SfM (Structure from Motion) techniques. Using both images, the study purposed to reduce the shadow areas that were found when using only aerial images. Accuracy of the two campaigns was assessed by root mean square error, and monitored by M3C2 (Multiscale Model to Model Cloud Comparison) method. The result of the M3C2 in closed areas such as sea cave and notch did not express the landforms partly. However, eroded debris on sea cliffs were detected as eroded area by M3C2, as well as in captured pictures by multi-camera. The result of this study showed the applicability of multi-camera and SfM in monitoring changes of sea cliffs.

• Journal of The Geomorphological Association of Korea
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• v.24 no.1
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• pp.93-104
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• 2017

The objective of this study was two fold: firstly, we analyzed how the Geoparks have been run since the first one had been designated on December 31th, 2015. We then investigated how visitors' geographical and geological recognitions on the parks have changes. We visited geosites and investigated how well these sites accorded with the conditions for running Geoparks. In addition, scenery pictures and hashtags uploaded in Instagram between 2015 and 2016 were collected in order to analyze visitors preferences on the geosites along the, Hantan Imjingang River Geopark. Results showed that the hotspots were Bidulginang Waterall, Art Valley, and Jaein Waterfall. Compared to the ratio of geographical and geological references in 2015, the hashtags in all of these three geosites increased. The increases were as much as 3% in Bidulginang Falls, 0.6% in Art Valley, and 5% in Jaein Falls. In labelling the geographical and geological terms in Bidulginang Falls and Jaein Falls, the most frequently mentioned hashtags was "columnar joint", followed by "natural monument", "Geopark", and "basalt canyon". This study includes the study of visitors recognition which is one of the most important, but somehow neglected factor for the geopark's management.

• Journal of The Geomorphological Association of Korea
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• v.17 no.2
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• pp.15-28
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• 2010

This study aims at the exploration of usefulness of traditional knowledge reflected in the place names. This study is useful and pragmatic for the establishment of disaster prevention measures from the analyses of disaster database, which shows the regional distribution and historical changes of disaster characteristics through history. The construction and categorization of disaster-related place names are based on historical maps and literatures on place names. One hundred twenty eight disaster-related place terminologies are selected based on disaster causes and possibilities. Design of field structures and category codes for the disaster-related place names has been proposed and the construction of disaster-related place names from the six sources has been completed.

• Journal of The Geomorphological Association of Korea
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• v.26 no.4
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• pp.47-65
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• 2019

A case study was conducted in Taean region to seek a more detailed macrotidal beach classification than existing beach classification models (Masselink and Short, 1993). Seepage and ridge & runnel were used for classification. On 20 beaches, 68 transects were surveyed 5 times using VRS-GPS. Cross-section area from the transect profiles, mean grain size from sediment analysis, significant wave height from Swan-wave modeling and beach embaymentization from aerial photograph analysis were used to identify the characteristics of the individual types. The transects were classified into 5 types in Taean region; Type 1: low tidal terrace, Type 2: low tidal terrace & ridge, Type 3: dissipative, Type 4: seasonal ridge, and Type 5: ridge & runnel. Generally, seepage was related to coarse sediment size and ridge & runnel was related to high significant wave height. Each type has different characteristics and there was a tendency between the types. The low tidal terrace type had coarse sediments, because this type is excluded from the littoral cell. In this study, the ridge and runnel type could be applied to the classification because the study area is limited only to the macrotidal environment in Taean region.

• Journal of The Geomorphological Association of Korea
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• v.27 no.3
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• pp.25-39
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• 2020

This study analyzed the management plan of Seomjin River Chimsil Wetland by identifying landscape changes through aerial photographs analysis and concentrations of sedimentation. Geophysical Landscape Change Analysis showed that vegetation accounts for more than half of the total area. The Barren land and water body was somewhere repeatedly increased and decreased and made an irregular form in the study area. The soil was acidic, and no eurtophication was shown, but it was potential to form wetland. In addition, the research area has been terrestrification of sand bar for a long period of time, forming a soil layer. Although the characteristics of river deposits were shown in the study area, the grain size was a particulate matter, and the sorting was 'very poorly sorted'. In some areas of Seomjin River Chimsil Wetland, sand bars were formed, but most areas were undergoing to terrestrification. Therefore, in order to preserve the riverine area and to serve by a bridge between the land ecosystem and the underwater ecosystem, it is very necessary to remove some vegetation, create a proper waterway, and restore the wetland.

• Journal of The Geomorphological Association of Korea
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• v.28 no.1
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• pp.35-50
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• 2021

In this study, we analyzed the changes in the topographical landscape and the sedimentary environment to evaluate the ecological value of the Dongcheon Estuary and protect the wetland, and presented the conservation management method of the Dongcheon Estuary. Based on the result of topographical landscape analysis, agricultural land tended to decrease continuously, and artificial structures gradually increased. Moreover, in sediment analysis, the Dongcheon Estuary showed both the characteristics of river sediments and coastal sediments, and in some areas problems such as acidification and nutritional imbalance appeared. Therefore, in order to protect and manage the Dongcheon Estuary with high ecological value, it is necessary to limit the development around micro topography and minimize the artificial damage in the Dongcheon Estuary. In addition, efforts such as securing facilities for reducing pollutants and freshwater wetlands for pollutants, that flow in from nonpoint pollutants are required.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.296-302
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• 2004

After the Rio declaration on environment and development in 1992, developed countries are undertaking 'environmentally sustainable transportation (EST)' projects. To meet the needs for EST, current transportation policies in Korea are rapidly reforming and one of its concerns is modernizing and upgrading railway freight system. Planning new railroad construction projects is increasing and subsequent environmental impact assessment (EIA) demands improvements, especially in both the EIA and decision making systems. In this paper, we discuss the present status of EIA for railroad construction projects, especially, by analyzing the EIA documents accumulated for last six years. The EIA for railroad construction projects .accounts for only $4.9\%$ of total project EIAs during 1998-2003. However, the portion is gradually increasing. Major environmental concerns for EIA in railroad construction projects were geomorphological and ecological changes, protection of rare organisms, air pollution, water quality, wast management, noise, etc. We also compared the characteristics of environmental impacts of railroad construction with those of vehicle road construction. The result shows that railroad construction usually requires 3${\~}$4 times longer tunnels and bridges for a given length than vehicle road construction. In addition, the amounts of geomorphological and ecological changes (road-cutting, embankment, devegetation, etc.) in railroad construction were generally less than $40\%$ of those in vehicle road construction. In order to develop environmentally friendly railway systems, monitoring studies for environmental impacts of railroads such as habitat fragmentation and road kills, dispersal of alien plants, tunnelling effects on groundwater and vegetation, and noise impacts are highly required.

• Journal of Environmental Impact Assessment
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• v.13 no.6
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• pp.295-305
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• 2004

After the Rio declaration on environment and development in 1992, developed countries are undertaking "environmentally sustainable transportation (EST)" projects. To meet the needs for EST, current transportation policies in Korea are rapidly reforming and one of its concerns is modernizing and upgrading railway freight system. Planning new railroad construction projects is increasing and subsequent environmental impact assessment (EIA) demands improvements, especially in both the EIA and decision making systems. In this paper, we discuss the present status of EIA for railroad construction projects, especially, by analyzing the EIA documents for the last six years. The EIA for railroad construction projects accounts for only 4.9% of total 918 project EIAs during 1998-2003, and the portion is gradually increasing. Major environmental concerns for EIA in railroad construction projects were geomorphological and ecological changes, protection of rare organisms, air pollution, water pollution, waste management, and noise, etc. We compared characteristics of environmental impacts of railroad construction with those of vehicle road construction, based on environmental and construction-planning indicators appeared in Environmental Impact Statements. Railroad construction usually requires longer tunnels and bridges for a given length than those for vehicle road construction. In addition, the amounts of geomorphological and ecological changes (road-cutting, embankment, devegetation, etc.) in railroad construction were generally less than 50% of those in vehicle road construction. To develop environmentally friendly railway systems, monitoring studies for environmental impacts of railroads such as habitat fragmentation and road kills, dispersal of alien plants, tunnelling effects on groundwater and vegetation, and noise impacts are highly recommended.