• Economic and Environmental Geology
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• v.55 no.4
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• pp.339-352
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• 2022

As environmental criteria items are increased or strengthened, cases of heavy metal contamination by geogenic origin are increasing, and the need to distinguish between natural and anthropogenic origins in soil or groundwater exceeding the standard is increasing. In this study, geochemical occurrences of geogenic heavy metals were identified through statistical processing of the national geochemical map data and evaluation of geochemical characteristics of regions with high geoaccumulation indices. Cobalt, Cr, Cu, Ni, Pb, V, and Zn were targeted for which the national geochemical maps were prepared, and Co, Cr, Ni, and V derived from ultrabasic or ultramafic rocks were classified as factor 1. Copper, Pb and Zn of non-ferrous sulfide origin were classified as factor 2. In particular, enrichment of heavy metals by factor 1 occurs mainly in the serpentine distribution areas of the Chungcheong region, and there is a risk of contamination in neighboring areas. In the case of factor 2, geogenic occurrence is concerned not only in non-ferrous metal mineralization areas such as Taebacksan and Gyeongnam mineralization zones, but also in Au-Ag mineralization areas distributed nationwide.

• Korean Journal of Environment and Ecology
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• v.17 no.1
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• pp.56-70
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• 2003

Reviewing the trend of land use in urban cultivated land, the large part of land has been changed into the high-profit cultivated land of green houses or the developing areas. So, its percent of cultivated land in land use comparing to the other types of cultivated land would get far higher. Therefore, this study aims to identify the characteristics of landscape ecological pattern in the cultivated land of green houses and to find its alternatives for management, which would be a basis of regional planning and management in terms of space and time. The cultivated land of green houses, whose its area reaches 19.3ha, in Seoul are mainly dispersed on the south eastern part of Seoul and its area is larger than the other types of cultivated lands. According to the result of shape index analysis, its perimeters were very simple. Also, Analyzing the first three major neighboring land use to the cultivated land of green houses, the most frequent biotope types of neighboring land use to the cultivated land of green houses were that transportation facility represented 60%, forest, 43%, the other types of cultivated land, 36%, and residential area, 33%. The cause why the percent of transportation facility was higher in the neigh-boring land use types was assumed for the production and distribution of crops. On the basis of the result of landscape ecological pattern analysis, the cultivated land would be managed and contributed to enhance biodiversity and urban environment preservation.

• Journal of the Economic Geographical Society of Korea
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• v.9 no.3
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• pp.341-357
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• 2006

Recently new periodic markets formed in large apartment areas where consumers live. Before, in the case of peasant periodic markets travelling merchants, consumers and producers met in specific places on decided dates. Closing time of apartment's new periodic markets is later than that of peasant periodic markets, and the number of travelling merchants is fewer than that of peasant periodic markets. The average number of apartment and household for a new periodic market is about ten and 920 respectively, and if neighboring apartment household are included, the number is larger. Apartment's new periodic markets in Cheongju city is included in Daejeon market area. The types of regional trip of travelling merchants can be divided into one round trip of two or three neighboring dongs and larger sphere of more than 4 dongs. The larger sphere round trip consists of one type combining the southeastern, southern and southwestern regions, and the other type combining southeastern and southwestern regions. About 85 percent of travelling merchants visit the periodic market 5 days in a week; about 12 percent of travelling merchants choose to visit on Saturday; only 2 percent of travelling merchants visit 4 days in a week.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.34.2-35
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• 2018

Galaxy transition from star-forming to quiescent, accompanied with morphology transformation, is one of the key unresolved issues in extragalactic astronomy. Although several environmental mechanisms have been proposed, a deeper understanding of the impact of environment on galaxy transition still requires much exploration. My Ph.D. thesis focuses on which environmental mechanisms are primarily responsible for galaxy transition in different environments and looks at what happens during the transition phase using multi-wavelength photometric/spectroscopic data, from UV to mid-infrared (MIR), derived from several large surveys (GALEX, SDSS, and WISE) and our GMOS-North IFU observations. Our multi-wavelength approach provides new insights into the *late* stages of galaxy transition with a definition of the MIR green valley different from the optical green valley. I will present highlights from three areas in my thesis. First, through an in-depth study of environmental dependence of various properties of galaxies in a nearby supercluster A2199 (Lee et al. 2015), we found that the star formation of galaxies is quenched before the galaxies enter the MIR green valley, which is driven mainly by strangulation. Then, the morphological transformation from late- to early-type galaxies occurs in the MIR green valley. The main environmental mechanisms for the morphological transformation are galaxy-galaxy mergers and interactions that are likely to happen in high-density regions such as galaxy groups/clusters. After the transformation, early-type MIR green valley galaxies keep the memory of their last star formation for several Gyr until they move on to the next stage for completely quiescent galaxies. Second, compact groups (CGs) of galaxies are the most favorable environments for galaxy interactions. We studied MIR properties of galaxies in CGs and their environmental dependence (Lee et al. 2017), using a sample of 670 CGs identified using a friends-of-friends algorithms. We found that MIR [3.4]-[12] colors of CG galaxies are, on average, bluer than those of cluster galaxies. As CGs are located in denser regions, they tend to have larger early-type galaxy fractions and bluer MIR color galaxies. These trends can also be seen for neighboring galaxies around CGs. However, CG members always have larger early-type fractions and bluer MIR colors than their neighboring galaxies. These results suggest that galaxy evolution is faster in CGs than in other environments and that CGs are likely to be the best place for pre-processing. Third, post-starburst galaxies (PSBs) are an ideal laboratory to investigate the details of the transition phase. Their spectra reveal a phase of vigorous star formation activity, which is abruptly ended within the last 1 Gyr. Numerical simulations predict that the starburst, and thus the current A-type stellar population, should be localized within the galaxy's center (< kpc). Yet our GMOS IFU observations show otherwise; all five PSBs in our sample have Hdelta absorption line profiles that extend well beyond the central kpc. Most interestingly, we found a negative correlation between the Hdelta gradient slopes and the fractions of the stellar mass produced during the starburst, suggesting that stronger starbursts are more centrally-concentrated. I will discuss the results in relation with the origin of PSBs.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.2
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• pp.455-464
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• 2015

Investments into existing cultural facilities are determined based on administrative district-based indices like population and area. Such macro judgment indices, however, fail to consider accessibility of cultural facilities from neighboring administrative districts and thus create problems including wasted budgets and duplicated investments. More recently, the government has made it a goal to increase the level of citizen awareness of these facilities, but achieving this requires the integration of neighboring administrative districts such that characteristics including transportation network and buildings are reflected in a comprehensive manner. This research therefore looks into Urban Network Analysis (UNA) as a means to investigate accessibility of cultural facilities. Use of UNA will make it possible to analyze the transportation network as well as building distribution, explained by building density, settled population, and other important building factors, in tandem, leading to the concentration of cultural facilities and the surrounding economic district being more properly reflected, and thus allowing for greater explanatory power in determining the level of accessibility. To test this, four target research districts were chosen from within the Gyeonggi Province and analyzed in terms of the accessibility of their everyday cultural facilities. Of the four districts of Gunpo, Anyang, Uiwang, and Gwacheon, accessibility of the first two districts, was found to be high, while accessibility was found to be relatively low for the latter two districts. This finding indicates that cultural facilities investments should be concentrated in the districts of Gunpo and Anyang.

• Korean Journal of Microbiology
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• v.35 no.1
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• pp.78-81
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• 1999

The change of soil microbial populations was studied at the burnt areas of Mt. Jirisan in Hddong-Gun, Kyungsangnam-Do, where the fire had occurred on Oct. 21 in 1997. On the first day of the fireextinguished, the microbial density (CFUIg dry soil) was investigated at the surface, 5 cm, 10 cm, 20cm, and 30 cm depth of soils. Bacteria at the surface and 5cm depth of burnt sites were estimatedwith the low density level of $10^2$ CFW/g soil comparing to the $10^6$ CFUIg soil of the neighboring unburntsites. Actinomycetes of burnt sites were completely disappeared at the surface, and were estimatedwith the low density level of $10^3$ CFUig soil at thc 5 cm depth comparing to the 10"CFUigsoil at the depth of unburnt sites. Fungi wcrc not isolated at the surface and 5 cm depth at all.However, the rarest lire was not found to decrease the microbial populalions at the lower depths than10 cm. In addilion, the recovery or soil microbial populations following the fire was bimonthly investigatedat the surrace and 5 cm depth. Most of microbial densities at the burnt sites were greatlyincreased two months after the fire, being enough to he compared with the neighboring unburnt sites.However, actinomycetes only at the surface of burnt sites still were estimated the low density level of$10^4$ CFUig soil 4 months after the fire comparing to the $10^6$CFIg soil of unburnt sites.TEX>CFIg soil of unburnt sites.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.639-648
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• 2011

We recorded the movement of wildbirds nine times at Hoam 1st Tunnel, Kkachisan Park, Deungneung pass to compare the movement between eco-corridor and neighboring crossing road from June to September, 2006. Among three areas, birds did not prefer the eco-corridor at pass type such as Kkachisan Park and Deungneung pass, however number of species and individuals were high at the eco-corridor at Hoam 1st Tunnel. Over 90m width and the slope location of eco-corridors can be beneficial for wild birds to enhance the movement along eco-corridors between isolated two patches. Average foliage volume under two meters showed the relation with bush nesters, and that from 7 to 8m had the highest relationship with canopy nesters. In Seoul city, target species should be considered at the construction of eco-corridors according to site characteristics, but Paradoxornis webbianus could be suggested as a main target species at eco-corridors. To enhance the movement of diverse wildbirds, we would implement that eco-corridors could be located at the slope area with the size of 1ha (over 90m width), eco-corridors could be planted and managed with the high foliage volume of shrub layer under twometers and canopy layer over 8 meters.

• Journal of the korean society of oceanography
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• v.37 no.4
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• pp.212-223
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• 2002

Cochlodinium polykrikoides bloom in 1995 was studied with a focus on an unusual coastal environment in the South Sea of Korea. Data on temperature, salinity, and zooplankton biomass during 1965-1998 and nutrients during 1990-1998 and chlorophyll-a during 1995-1998 were used in this study. These data were obtained from the serial oceanographic observations in Korean waters carried out by the National Fisheries Research and Development Institute. In 1995 the C. polykrikoides bloom began in the coastal area around Narodo Island in August and consequently occurred to the whole coastal area of the South and East Seas of Korea. During June-October 1995, the coastal environment was unusual compared with the long-term means during 1965-1998. In June 1995, sea surface temperature was 1-2$^{\circ}C$ warmer than in other years in all coastal areas, while salinity was high only to the east of Jeju Island. In August 1995, a strong coastal front appeared inshore of a line between Jeju and Tsushima Islands. In particular, a strong coastal front which showed the characteristics of upwelling front occurred in the coastal area around Narodo and Sorido Islands, not only because of a strong intrusion of the Tsushima Warm Current but also because of the upwelling of cold bottom water. Salinity was low in the neighboring waters of western side of Jeju Island. Nutrients and chlorophyll-a were high in the inshore area between Narodo and Sorido Islands in 1995 in contrast with the other years and areas. Zooplankton showed an unusually high abundance in the coastal area in October 1995. We conclude that the Tsushima Warm Current strongly influenced the South Sea of Korea in 1995 and created strong upwelling front bordering cold upwelled water in the coastal area around Narodo and Sorido Islands. It leads us that these physical structures introduce the favorable environment for the development of C. polykrikoides blooms. We suggest that C. polykrikoides has a bio-physical tolerance of high shear and stress and prefers frontal and upwelling relaxed areas as its habitat. We also find that nutrients were not supplied to the coastal area from the offshore where a low salinity water mass with high nutrients appeared around Jeju Island. Because the strong upwelling front protect the reach of offshore low saline water mass. The main source of nutrients was the upwelled water mass in the coastal area of Wando-Narodo-Sorido.

• Journal of the Korean Geographical Society
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• v.49 no.5
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• pp.656-674
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• 2014

The objective of this study was to examine the distinctiveness and generality of landforms of the Korean peninsula, and further discover geomorphological principle that can be applied to land and environmental management in Korea. The research targeted East Asia and Korea, with terrain analysis conducted at a continental scale, national scale, and regional scale sequentially. East Asia displays complicated characteristics and evolutionary history of geotectonics, but exhibits distinct northeast-southwest geomorphological structure and connectivity at the continental level. While the Korean peninsula follows this pattern on a continental scale, it also features NNW-SSE direction (Nangrim and Taebaek Mountains) geomorphological connectivity that intersects at a right angle. From a national perspective, the Korean peninsula hosts the most diverse geomorphological features within East Asia. It does not have a high average altitude, but has relatively high slope angle and intricate topographical distribution in comparison to neighboring areas. While the mountains and plains of the Korean peninsula display a smooth connection, geomorphologically similar areas such as Shikhote-Alin, Huanan in China, and Japan have clear characteristics that divide the mountains and plains. Despite the distinctiveness and diversity that appear in East Asian topography on the regional scale, the connectivity that links the top of mountain (hill) to stream is identical among all areas as a general rule. It is collectively considering the connectivity and the geomorphological and ecological processes that arise within this connectivity that will serve as the focal point for sustainable landscape management.

• Journal of the Korean Geographical Society
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• v.38 no.5
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• pp.725-740
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• 2003

The National Land Planning and Use Law Act at the beginning of 2002, introduced Land Suitability Assessment System(LSAS) in order to mitigate conflicts between development and conservation needs for land. LSAS is to assess land characteristics according to its physical, locational, and environmental characteristics, and then to classify it into several categories based on its usability. This study aims to review the factors to determine the suitability of the land and their weights. Land suitability is determined by a variety of factors, such as land-surface slope and altitude, the type of land use in neighboring areas, accessibility to public facilities and existing developed areas, and ecological characteristics of the land. This article analyzed these factors and their influences by using the Delphi survey and Analytic Hierarchical Process. One of the most influential factors on the development suitability of land is the distance to developed areas and public facilities. On the other hand, the slope and altitude of the land have comparatively low influences on the land development. The coverage of prime cultivating land of the neighbouring region and slope of the land are analyzed as important factors on the agricultural suitability of the land. The ecological features and the ratio of conservation area in the neighbourhood are counted as the most important factors in determining the land for conservation. This article tested these factors and their weights in assessing land suitability of land as a case study.