• The Korean Journal of Soil Zoology
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• v.5 no.2
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• pp.101-112
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• 2000

Spiders usually have poor vision but not the jumping spiders. Their eight eyes are located on its distinctive box-shaped head and relatively well developed. The Spiders were fixated with 3% glutaraldehyde and thin section was performed with ultra-microtome. The specimens were observed with light microscopy, transmission and scanning electron microscopy. Eye area of jumping spider is competed of three rows. The first eye row comprise four eyes. Among them, two anterior median eyes are the largest and two anterior lateral eyes are relatively small. The former are main-eyes and have excellent vision. The second row, which has the two smallest eyes, is located about midway between the first and third rows. The third row is about half-way back on the thorax and eyed of which are middle size. To investigate ultrastructure of salticid spiders'eye, Menemerus fulvus was chosen. All of Menemerus fuvus's eyes are composed of cornea, lens, vitreous body and retina in histologically. Cornea layer, linked to exocuticle of exoskeleton. is regular layer structure without any cell tripe. Lenses are biconvex type. Retinas comprise well developed microvilli-shape rhabdomeres, unpigmented supporting cells, and pigmented cell. Retinas of anterior median eyes are surrounded by circular cylinder-shaped vitreous body, photoreceptor, i.e. rhabdomeres, of it is irregularly arranged compared to the other eyes.

• Korean Journal of Environment and Ecology
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• v.30 no.4
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• pp.783-792
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• 2016

The purpose of this study is to investigate the characteristics of the vegetation structure and the location environment of Albizzia kalkora (AK) growing in Mt. Yudal located in Mokpo city and in the nearby islands. The AK community in Mt. Yudal in Mokpo city (Community I) is located in a region which is relatively high above the sea level. The average age of the major kinds of trees found in the region is about 30 years. The vegetation structure in the community shows an early stage of vegetation development due to continued disturbance. In Community IV, on the sandy soil in the flatland near the seashores, the average age of the major kinds of trees is about 9 years. In this community, a pure forest is presumed to have been formed in a poor environment which is artificially disturbed in relatively recent times even as AK with its strong adoptability was introduced into the region. In other communities (II, III), the vegetation state shows a competition between AK and deciduous oak trees, and the average age of the major kinds of trees is about 13 to 30 years. AK communities with a better developed vegetation structure are located on the higher steep slopes near the seashore. In the early stage of vegetation development, the forest floor received more effective light for photosynthesis, and thus more seedlings of AK emerged and grew. The probability of AK appearing in the damaged or sterile soil near the seashore was high because of its strong adaptability. However, as the vegetation structure developed further and the soil fertility increased, the domination of AK in the vegetation structure decreased as deciduous oak trees won the competition with AK.

• Journal of Gifted/Talented Education
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• v.13 no.1
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• pp.65-80
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• 2003

The purpose of this study was to investigate the Asynchronous development of young gifted children by parents' perception. Total 3 groups of 145 subjects from age 30 months to 6 years 10 months old young gifted children's parents participated. The major findings were as follows: (1) The mean developmental characteristics was at a high average level. The developmental subscales tended to be high. The level of verbal understanding/expression tended to be high. It reared as followed; intellectual capacity, emotional maturity, visual-motor coordination, morality, self-behavior control, emotion control, physical development, social development, peer relationship, leadership ability. (2) There were significant differences between intellectual capacity, verbal understanding /expression and physical, social development, self-behavior control, emotion control. There were significant differences between physical development, self-behavior control and emotion control as children got lower. There were significant differences between verbal understanding/expression and visual-motor coordination as children got older. There were significant differences between social development, peer relationship and self-behavior control, emotion control as children got older. Also, there were significant differences between leadership ability and self-behavior control, emotion control as children got older. There were significant differences between morality and self-behavior control as children got older. These findings suggested that young gifted children were in the special needs because of the developmental differences.

• The Korean Journal of Mycology
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• v.44 no.1
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• pp.16-22
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• 2016

Five islands (Sinjindo, Mado, Daenanjido, Wonsando, and Sapsido) and the coastal area (Muchangpo) in Chungnam, Korea, were selected to determine the diversity of arbuscular mycorrhizal (AM) fungi. Soil-inhabiting AM fungi were isolated and identified on the basis of morphological characteristics and sequence analyses of 18s rDNA. The differences in the fungal community structures were compared among sites. As a result, 24 species of AM fungi were identified, of which two species of AM fungi, Acaulospora brasiliensis and Redeckera fulvum, were isolated for the first time in Korea. This study revealed that AM fungal spore abundance was low and the genus Acaulospora was dominant in most of the islands. AM fungal community structures in five Islands were highly similar. However, the coastal area, Muchangpo, had different AM fungal community structure from the islands.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.2
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• pp.131-137
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• 1989

Chemical and microbial characteristics of root zone of neighboring large and small ginseng in a high yield field were investigated in relation to root growth. $NO_3-N$, $NH_4-N$, and available P contents were significantly low for large root but Ca high. The contents of $NO_3-N$ or $NH_4-N$ showed significant negative correlation with fine root development. Precipitation quotient of humic acid tended to be high for large roots. The population of one dominant bacteria was significantly high for large root. The ratios of bacteria to fungi or actinomycetes were positively correlated with fine root development.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.72-75
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• 2005

본 연구에서는 야외규모 TCE (trichloroethylene) 질량전이역학을 평가하기 위해 TCE의 대수층 내 유입 및 용해상 거동을 고해상도 수치 모사를 실시하였다. 공간적으로 불균질한 대수층 $10{\times}10{\times}10m$ 도메인 내부의 유입된 TCE 분포를 모사하기 위해 본 연구를 통해 개발된 정성적 침투모델(percolation model)이 이용되었다. 이를 기초로 하여 연계되어진 (coupled) 지하수 유동 및 용해상 거동 장기 (long-term) 모사를 실시하였다. 지엽적으로 일어나는 질량전이는 기존 연구를 통하여 발표되어진 실험실규모 연구에 기초하였다. 지하수가 도메인을 지나 흘러나가는 경계면에서 측정되어진 용해상 (aqueous phase) TCE의 질량선속 (mass flux)을 통해 실질 야외규모 질량전이 상수가 계산되었다. 관찰된 바 야외규모 질량전이 상수는 실험실 연구를 통해 측정된 값에 비하여 휠씬 작은 값을 보였으며 이는 지하수 유속 및 TCE의 불균질한 분포에 기인한다. 야외규모 질량전이 상수는 평균 지하수 유속에 직접 비례하는 것으로 관찰되었고 이는 기존 실험실 연구를 통해 알려진 평균 지하수 유속의 0.7승이라는 결과와 대조되는 것이다. 또한 모사를 통해 관찰된 야외규모 질량전이 상수는 상대 TCE 질량의 고갈상수 승에 비례함을 보였다. 이러한 고갈상수는 TCE가 측방으로 퍼지는 현상이 강한 대수층, 즉 저투수성 층의 발달이 양호한 대수층, 에서는 1보다 작은 값을 갖고 그렇지 않은 대수층, 즉 저투수성 층의 발달이 미약한 대수층, 에서는 대체적으로 1보다 높은 값을 갖는 것으로 관측되었다. 이는 DNAPL의 측방 퍼짐이 강한 대수층에서는 용해로 인한 시간에 따른 오염원 부근에서의 농도 감소가 미약하기 때문인 것이며, 그와 반대로 DNAPL의 측방 퍼짐이 약한 대수층에서는 시간이 지남에 따라 용해에 의해 지속적으로 오염원 부근에서의 농도가 감소 또는 소멸함으로 인하여 측정되는 용해상 DNAPL의 질량 선속 역시 계속적으로 감소되는 것으로 밝혀졌다.

• Journal of the Korean GEO-environmental Society
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• v.8 no.5
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• pp.5-14
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• 2007

The quantity of noxious wastes generated by the growth in industrialization and population in all over the world and its potential hazards in subsurface environments are becoming increasingly significant. The extraction of the contaminant from the soil and movement of the water are restricted due to the low permeability and adsorption characteristics of the reclaimed soils. Incorporated technique with PVDs have been used for dewatering from fine-grained soils for the purpose of ground improvement by means of soil flushing and soil vapor extraction systems. This paper is to evaluate several key parameters that affected to the performance of the PVDs specifically with regard to: well resistance of PVD, zone of influence, and smear effects. In the feasibility of contaminant remediation was evaluated in pilot-scale laboratory experiments. Well resistance is affected on the vertical discharge capacity of the PVDs under the various vacuum pressures. The discharge capacity increases consistently in areal extents with higher applied vacuum up to a limiting vacuum pressure. The head values for each piezometer at different vacuum pressures show that the largest head loss occurs within 14 cm of the PVD. Air flow rates and head losses were measured for the PVD placed in the model test box and the gas permeability of the silty soils was calculated. Increasing the equivalent diameter results in a decrease in the calculated gas permeability. It is concluded that the gas permeability determined over the 1,500 to 2,000 $cm^3/s$ flow rates are the most accurate values which yields gas permeability of about 3.152 Darcy.

• Economic and Environmental Geology
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• v.52 no.5
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• pp.381-393
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• 2019

Carbonate breccias occur sporadically in the Middle Cambrian Daegi Formation on the southern limb of the Baegunsan Syncline, Taebaeksan Basin. These carbonate breccias have been largely interpreted either as sedimentary breccias or as tectonic, fault-related breccias. Recent study, however, indicates that the majority of these breccias are a solution-collapse breccia which is causally linked to the paleokarstification. Extensive karstification is attributed to prolonged subaerial exposure of the carbonate platform. The exposed surface is a record of interruption in sedimentation on the carbonate platform. In the stratigraphic record, such karst-related post-depositional features are recognized as meteoric diagenetic features, paleosols, and solution-collapse breccias. Solution-collapse breccias are particularly well preserved and most profound in the carbonate rocks below the major unconformities, which also are evidence of prolonged subaerial exposure. The Middle Cambrian Daegi Formation provides an example of solution-collapse breccias. The formation and preservation of the solution-collapse breccias imply that a stratigraphic discontinuity surface (unconformity) can be designated within the Daegi Formation.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.6
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• pp.373-379
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• 2001

The weathering rates and change of chemical composition of 6 residual Entisols derived from granite, granite-gneiss, limestone, sandstone, shale, amd basalt in Korea were studied. The chemical composition of each profile with parent rocks were determined using XRF with the physico-chemical properties and the morphology of soils. In the A horizons of all the soils except Euiseong series, the content of clay, organic matter and cation exchange capacity(CEC) showed higher than those of C horizon, but bulk density and pH showed lower than C horizon. Clay content in the soil from sandstone was decrease with soil depth, which may caused by the elluriation. In total element analysis. $SiO_2$ was high in the soil from granite. granite-gneiss, sandstone and compare with basalt and limestone. $Fe_2O_3$ and MgO was high in the soil from basalt, limestone and shale compare with granite. granite-gneiss and sandstone. And ignition loss was particularly high in the soil from basalt and limestone. The rate of element loss was higher in base cations(Ca, K, Mg, Na) than Si, Al, Fe in the soils. The concentrations of $TiO_2$ in the A horizon compare with that of the C horizon was due to resulting from losses of other less stable elements existed. Considering with relative rate of each elements in soils, $SiO_2$ and $Al_2O_3$ which originated from sandstone and granite, granite-gneiss, sandstone, shale, and basalt were lost higher than those from lime tone, but loss of basic cations were more in the soil from limestone which may be rapid weathering of calcite. The magnitude of losses of the overall elements were increased in the order of the soils from sandstone and granite ${\gg}$ limestone and shale) granite-gneiss and basalt.

• Journal of the Korean association of regional geographers
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• v.11 no.5
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• pp.368-382
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• 2005

This paper deals with the village names in Geoje City[Geoje Island], Hundreds of village names in the city are found to be based on some environmental features such as landforms, weather, and soil of the island. A considerable number of village names in the city are derived from the mountainous landforms with steep slopes or from the extremely indented coastlines with many small islands, and some village names are originated from the weather and soil. In this paper, it is realized that the village names often reflect the environments perception of the residents and that they can give some clues to the environment's changes of the places.