• Journal of the Korean Geographical Society
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• v.35 no.2
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• pp.159-176
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• 2000

본 연구는 남한강 상류의 소지류인 쌍천 유역에 발달한 하성단구의 퇴적물을 모재로 발달한 토양 특성을 조사.분석하였다. 중위 단구의 A1층은 갈색(10YR 4/3)의 미사질토양이고 발달도가 낮은 입상구조이며 B1층은 황갈색(10YR 5/8)의 사질식양토로 아각괴상구조이다. 고위단구의 A1층은 옅은 적갈색(5YR 4/3)의 미사질양토 내지 황갈색(10YR 5/8)의 미사질식토로 발달도가 낮은 아각괴상구조이다. B1층은 적색(2.5YR 3/6)의 사질식토 내지 밝은 적갈색(2.5YR 4/6)의 식양토로 발달도가 양호한 아각괴상구조이다. 고위단구 퇴적층을 모재로 발달한 토양의 구조는 중정도의아각괴상구조이고 조직이 치밀하다. 토양은 A1층, B1층,B2층으로 되어 있으며 또한 B층은 점토가 집적되어 있고 점토 피막이 나타난다. 쌍천의 중위단구상에 발달한 토양은 황갈색토이고 고위 단구상의 토양은 적색토이다. 고위단구 퇴적물을 모재로 발달한 본 적색토는 생성시가가 민델-리스 간빙기의 이전에 생성된 것으로 현재보다 온난한 생물-기후 조건하에서 탈규산화를 동반하는 적색토화작용에 의해 형성된 것으로 추정된다. 고위단구에 발달한 적색토는 토양단면의 형태적 및 물리 화학적인 특성등으로 보아 고적색토로 분류된다.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.229-229
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• 2021

최근 이상기상으로 국지성 집중호우가 빈번하게 발생함에 따라 토사유출에 의해 피해가 증가하고 있다. 급경사 사면을 갖는 교란산지와 개발지의 경사면은 토양침식 위험에 노출되어 있다. 특히 지표유출수의 집중흐름에 의한 세류발달은 세류간침식에 비해 많은 토양침식과 토사유출을 발생시킨다. 이러한 급경사 사면에서의 세류발달에 대한 수리학적 메터니즘과 한계조건을 파악하고자 강우와 유입수 모의를 통한 토양침식 실험을 수행하였다. 강우와 유입수의 상호작용에 의한 세류발달의 특성과 토사유출량 증가를 파악하고자, 강우량의 증가와 유입수 유무에 따른 실험이 이루어졌다. 강우강도의 범위는 100~140mm/hr이고, 유입수는 170ml/s 이였다. 유입수량은 합리식으로 계산하였으며, 토양상자 상단에서 균등분사식으로 유입되었다. 세류발달의 수리학적 특성치를 취득하기 파악하기 위해, 염료주입 지표수 거동에 대한 동영상을 판독하였다. 세류발달은 유입수가 없는 경우 3분 이내 그리고 유입수가 있는 경우 30초 이내에 발생하였다. 토양상자내의 평균 유속범위는 7.83~29.27 cm/s 이였다. 실험에서 발달된 세류는 15분경과 후부터 평형상태를 유지하였다. 경사실험조건별로 세류 차수분석을 위해 각 세류의 최대길이, 폭, 넓이를 측정한 결과 세류의 차수는 강우만 있는 경우 1~2차로 발달하였으며, 유입수가 있을 때는 2~3차로 발달하였다. 지표유출이 증가하면서 세류발달의 개수는 줄었지만 규모는 더 크게 나타났다. 세류가 발달하는 시점의 한계유속은 10~20cm/s 범위인 것으로 파악되었다. 지표유출이 증가하면서 세류의 발달도 더 심화되지만, 동일한 강우에 일정시간동안 노출되면서 세류는 평형상태가 되어 더 이상 침식이 활발하게 진행되지는 않았다. 유입수가 있는 조건에서 수량은 약 2배가 증가하였지만, 토사유출량은 세류확장에 의해 약 4배가 증가하는 것으로 나타났다.

• Journal of Conservation Science
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• v.7 no.2
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• pp.68-79
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• 1998

The protecting-chamber for a standing Buddha of Mireuk-ri temple site at Jungwon is composed of granite of Cretaceous age which mainly consists of quartz, perthite, plagioclase, and biotite with minor amounts of muscovite, apatite, chlorite, sericite and opaque mineral. There are abundant cracks which may be developed by strong weathering and differential loading by structural unbalances of the whole protecting-chamber. Cracks can be divided into three types based on genesis as those formed by exfoliation, intrinsic, and pressure. The exfoliation occurred along the onion structure of the granite. The pressure cracks are generally superimposed on the exfoliation ones, which might be developed by structural unbalance of the protecting-chamber resulted from differential loading in places. The structural unbalance may be due to change in physical properties of the rocks according to strong weathering, differential settling of basement soil by difference in loading in places of protecting-chamber, westward creep of the basement soil below the West wall and related different resistance of the basement soil against the loading, and partial depression of the West wall. For the conservation of the protecting-chamber, it must be considered the method of stabilizing the basement and treatment of the cracks.

• Journal of The Geomorphological Association of Korea
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• v.19 no.2
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• pp.81-98
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• 2012

This research aims 1) to analyse the spatial occurrence of red soils, in Korea 2) to predict their spatial distribution using terrain analyses, and 3) to interpret results from the perspective of pedogeomorphological processes. Red soils (often called red-yellow soils) in Korea are frequently found on welldrained plains and gently sloping areas. These soils are widely believed paleo-soils that were formed under hot and humid climatic conditions in the past. The spatial distribution of red soils was derived from the soil map of Korea, and a DEM based soil prediction was developed, based on a continuity equation to depict water and material flows over the landscape. About 64.5% of the red soil occurrence can be explained by the prediction. Close examinations between surveyed and predicted red soil maps show few distinctive spatial features. Granitic erosional plains at the inland of Korea show comparatively low occurrence of red soils, which might indicate active geomorphological processes within the basins. The occurrence of red soils at limestone areas is more abundant than that of the predicted, indicating the influence of parent materials on the formation of red soils. At and around lava plateau at Cheulwon and Youncheon, the occurrence of red soils is underestimated, which might partly be explained by the existence of loess-like surface deposits. There are also distinctive difference of prediction results between northern and southern parts of Korea (divided by a line between Seosan and Pohang). The results of this research calls for more detailed field-based investigations to understand forming processes of red soils, focusing on the spatial heterogeneity of pedological processes, the influence of parent materials, and difference in uplift patterns of the Korean peninsula.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.6
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• pp.478-485
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• 2009

This study was conducted to reclassify Yongheung series based on the second edition of Soil Taxonomy and to discuss the formation of Yongheung series in Jeju Island. Morphological properties of typifying pedon of Yongheung series were investigated and physico-chemical properties were analyzed according to Soil Survey Laboratory Methods Manual. The typifying pedon contains 3.2~3.4% oxalate extractable (Al + 1/2 Fe), less than 85% phosphate retention, and higher bulk density than $0.90Mg\;m^{-3}$. That can not be classified as Andisol. But it has an argillic horizon from a depth of 15 to 150 cm and a base saturation (sum of cations) of less than 35% at 125 cm below the upper boundary of the argillic horizon. That can be classified as Ultisol, not as Andisol or Alfisol. The typifying pedon has 0.9 % or more organic carbon in the upper 15 cm of the argillic horizon and accordingly, can be classified as Humult. It has a clay distribution in which the percentage of clay does not decrese from its maximum amount by 20% or more within a depth of 150 cm from the mineral soil surface, and keys out as Palehumult. Also that meets the requirements of Typic Palehumult. That has 35 % or more clay at the particle-size control section and has mesic soil temperature regime. Yongheung series can be classified as fine, mixed, thermic family of Typic Palehumults, not as fine, mixed, thermic family of Typic Hapludalfs. Most soils distributed in the southern coastal areas in Jeju island which have a humid climate are developed as Andisols. But Yongheung series distributed in this areas and derived from mainly trachyte, trachytic andesite, and volcanic ash are developed as Ultisols.

• Journal of the Korean earth science society
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• v.27 no.5
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• pp.548-556
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• 2006

The purpose of this study is to clarify the relict landform development of fluvial terrace and the soil characteristics occurring on the fluvial deposits. The physico-chemical properties of soil that are developed on terrace deposits and X-ray diffraction analysis of clay were investigated specifically. The horizon of $A_1$ consists of silt loam with reddish-brown color (5YR4/3). Its soil structures is a weak, fine, subangular, and blocky, breaking to granular. The horizon of $B_{1t}\;and\;B_{2t}$ are silt clay with either a yellowish red (5YR5/6), bright red (2.5YR4/6) color. This soil structure is weak, subangular, and blocky, with thin discontinuous bright red (2.5YR4/6) clay cutans and soft manganese concretions. This red soil structure is made on heavy-textures. It is packed compactly with parent materials of high fluvial surface sediments, and usually has a $A_1-B_{1t}-B_{2t}-C$ profile, from top to bottom. In most cases, clay accumulation in the B-horizon and clay cutans on ped surfaces are observed, which means the argillic horizon has formed. The soils derived from fluvial surface deposits are associated with soils. The soils on the high fluvial surface are considered to be a kind of paleo-red soil which were developed by strong desilicification and rubefaction, and strong leaching of bases under warmer bio-climatic condition during the old Pleistocene period. According to these morphological and anlaytical characteristics,geomorphological features and bio-climatic conditions under which the soil have developed on the high terrace sediment indicate that the soil should be classified as paleo-red soils.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.143-144
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• 2002

동아시아지역의 산업발달로 인하여 증가한 대기중의 에어로솔들은 도시지역 시정장애의 주요 요인으로 작용하며 강우의 산도를 증가시켜 토양의 산성화를 야기하고 또한 장거리 이동하여 청정지역의 대기오염농도에 주된 요인으로 작용하고 있다. 동아시아지역의 대표적인 오염물질 장거리 이동현상인 황사는 중국에서 발생한 dust storm이 주변 산업지역의 오염된 공기와 이동, 인접국가의 대기오염농도에 직접적인 영향을 끼치는 현상으로 발생빈도는 년간 3-5회 정도 발생한다. (중략)

• Journal of the Korean earth science society
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• v.26 no.8
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• pp.828-835
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• 2005

The purpose of this study is to clarify the landform development of fluvial terrace and the soil characteristics occurring on the terrace deposit. In order to achieve the purpose, the characteristics of soil profiles, the physic-chemical properties of soils that are developed on terrace deposits and X-ray diffraction analysis of clay were investigated. The horizon of Al in the high fluvial surface is silt clay loam of red (2YR 4/6). The soil structure is a developed granular structure. The horizon of B1 is silt clay reddish-brown (2.5YR 4/6). The soil structure is a medium subangular blocky structure. This red soil structure is made on heavy textured and compactly packed parent materials of high terrace sediments and usually has A-B-C profile. In most cases, clay accumulations in B-horizon and clay cutans on ped surfaces are observed, which mean the formation of agrillic horizon. As the result of this study, soils derived from fluvial terrace deposits on high fluvial surfaces are considered paleo-red soil which were developed by pedogenese-strong desilicification and rubefaction and strong leaching of bases- under warmer bio-climatic condition during in the old Pleistocene period.

• Journal of the Korean association of regional geographers
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• v.12 no.4
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• pp.437-448
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• 2006

Bare-topped thufur is called as frost scars, implying the rupturing stage of vegetated mounds, Field observations and measurements provide empirical information on the process and factors of thufur disintegration in Mt. Halla, Initial bare patches on mound apexes are scaled up by continuous removal of soil and vegetation, resulting in the formation of crater-like thufur, Frost action plays a primary role in thufur disintegration, In particular, pipkrake loosens soil particles within the bare patches and subsequently accelerates the degradation of vegetated mounds during periods with frequent diurnal freeze-thaw cycle and high soil moisture, Deflation also has an impact on thufur breakup in that the bare patches usually lack upper dark brown soil and are covered with granules, Withered shrubs such as Juniperus chinensis var. sargentii are frequently observed in frost scars and disrupted mounds, indicating that thufur disintegration has been probably influenced by global warming.

• Economic and Environmental Geology
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• v.37 no.3
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• pp.325-334
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• 2004

Detail downward variation records for paleomagnetic, XRD, photospectrogram, TOC results were obtained from the soil developed along the Hantan River, Gungpyeong-ri, Cheongsan-myeon, Yeoncheon-gun Gyeonggi-do. The unconsoildated sediments underlain by the Jeongok Quaternary Basalt indicates that the paleosol formed twice with different ages, as apparently indicated by sedimentological, paleomagnatic, and soil chemical properties. The paleosols recorded paleoclimate and paleoenvironments of about 271.21$\pm$89.8 ka before eruption of the Quaternary Jeongok Basalt.