• Journal of the Korean Geographical Society
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• v.42 no.6
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• pp.898-913
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• 2007

We examined soil properties and provenance of loess-paleosol sequences at the Daebo Granite area of Buan, Jeonbuk Province, South Korea. The section consists of the surface layer, Layer 1(paleosol), Layer 2(loess), Layer 3(paleosol), Layer 4(loess), and Layer 5(paleosol), from top to bottom and thickness of the exposed section is approximately 280cm. The magnetic susceptibility values show the distinct variations between the loess- and the paleosol layer. Even though pH, ORP, water content, and soil hardness do not display the obvious differences in the section, the organic content indicates the variation similar to those of the magnetic susceptibility. In the respect of the soil colors measured under 3 conditions, although the variations of the wet soil color exceedingly reflect the difference of the layers, these variations are obscure in some points in the section due to the characteristics of the Munsell color system. Based on the geomorphological properties, sedimentary structure, the difference of the major element composition and the condrite-normalized rare earth element(REE) patterns showing the clear difference from the adjacent bedrocks and stream sediments and the similarity to those of the Chinese Loess Plateau, it is suggested that the section was formed by the material originated from the Chinese Loess Plateau and peripheral areas. However, because the material experienced the alteration after sedimentation under the environment of the sediment area, it has the properties different from the material in the provenance areas. This phenomenon may result in the climatic condition of Korea, especially in precipitation.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.4
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• pp.265-270
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• 1989

Soil properties for the limestone-derived soil were examined to relate soil formation to stratigraphy of parent materials and hillslope positions in Bangjeol Ri, Yeongweol Eup, Gangweon Do. Pyeongchang, Anmi, Yulgog and Mungyeong series were described for topographic positions such as shoulder position, footslope, terrace and local bottom associated with toposequence where the landscape consisted of gently rolling hillslopes and nearly level plains. 1. Pyeongchang, Anmi, Yulgog and Mungyeong series had the standard hue of the 2.5YR, 5YR, 10YR and 2.5Y, respectively. Thus, color sequence of soil could be related to hillslope positions on the landscape. 2. With ascending slope toward summit, the clay content increased while silt content decreased 3. Silt/Clay ratios ranged from 0.27 to 3.76 and it was increased with descending to bottom. It, also, appeared that maturity of soil was higher at summit position than at bottom. 4. Soils developed in limestone were neutral in soil reaction and very low in available $P_2O_5$. OM, available $SiO_2$, CEC, and active Fe in soils seemed to be increased with ascending to summit position.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.5
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• pp.348-354
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• 2009

We analyzed relationship soil distribution and climatic factors using temperature, precipitation and evapotranspiration maps in Jeju island. The whole area was divided into 5 groups - mesic high moisture region(group1), thermic high moisture region(group2), thermic balanced moisture region(group3), thermic short moisture region(group4), thermic very short moisture region(group5), by soil temperature and monthly moisture balances. By the sequence from group1 to group5, the occupation ratio of soils was increased in order of andisols, inceptisols, alfisols, ultisols in soil orders, and of black soils, very dark brown soils, dark brown soils in soil colors.

• Journal of the Korean association of regional geographers
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• v.18 no.1
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• pp.17-26
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• 2012

In Hwangtohyun, meaning 'red soil pass', reddish surface mantles is widespread. Other granitic hills, exceptionally Naju and Youngam area, in Korean peninsula don't commonly have that color. This paper attempts to address this issue by CIA(chemical index of alteration). CIA data and A-CN-K diagram provide crucial insights into the changes in the relative contributions of chemical physical weathering in difference of grus regolith and saprolite. CaO and $Na_2O$ show strong depletion and $K_2O$ is progressive loss. In grus regolith, weathering trends are (sub)parallel to the CN-A join of the A-CN-K diagram, but the sample's composition plot ever closer to the A-K join in saprolite. The difference of weathering trend obtained using CIA data corresponds closely with the visual interpretation of soil color and texture.

• Journal of the Korea Organic Resources Recycling Association
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• v.7 no.1
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• pp.23-30
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• 1999

The changes of soil physico-chemical properties were investigated in the sandy loam soil amended with various application rates of chicken and pig manure composts. After repeated application of the composts for 3 years, total nitrogen content in soil treated with applied 120Mg/ha of chicken and pig manure composts was 2.1 g/kg equally. Organic matter content was 38.8 and 39.1 g/kg, available phosphate content was 602 and 585 mg/kg, and cation exchange capacity(CEC) was 10.1 and 12.4 cmol/kg in chicken and pig manure compost 120 Mg/ha treatment, respectively. Exchangeable K, Ca, Na, Mg contents, and electrical conductivity(EC) increased with the amount of applied compost. Also, with increased amount of applied compost, porosity of soil increased, but hardness, bulk density and Y value decreased.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.3
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• pp.276-281
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• 1985

This study was conducted to examine the morphological, physical and chemical characteristics of the Song-jeong (residuum), Dae-gog (local colluvium-alluvium), Ji-san and Og-cheon (local-alluvium) series with fine loamy texture derived from fine granitic parent materials on the drainage catena. 1. These soils consist of a catena, and then a color sequence due to the influence of topography, water table and free iron content. 2. The poorer the drainage, the higher were the silt/clay ratio, soil reaction, organic matter, and available phosphate content in soils but the active iron content was lower.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.3
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• pp.260-264
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• 1985

Ferrallitique soils are real tropical soils, with an oxic B horizon such a horizon is at least 30cm thick, has > 15% clay, diffuse horizon boundaries, no weatherable minerals and a CEC of clay < 16 me per 100g. These soils are in general the real reddish or yellowish very uniform tropical clay soils with an orchric A horizon and a deep B horizon, otherwise almost characterless. The soil profile looks uniform and maybe some metres thick. It is well drained, has a good permeability and a stable structure. As there is little or no weatherable mineral, because these soils are old and exhausted of bares, natural fertility is very low. There has been a complicated process of soil formation. Intensive and continuous weathering over a very long period has resulted in leaching of bases and silica, in relative accumulation of resquioxides and in formation of kaolinitic clay. Until recently, there has been much confusion in classifing and naming tropical soils. Particularily what are now Ferralsols in the FAO scheme, and Oxisols in Soil Taxonomy. Old names of various classification system are: Lateritic soils, Latosols, Ferrallitic soils. For agriculture, these soils are important, but chemically very poor, not only because of a low CEC but also because of deficiency of bases, especially Ca, Mg, and K, strong P fixation and high exchangeable Al percentage.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.704-710
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• 2012

The lower portion of sloping paddy fields normally contains excessive moisture and the higher water table caused by the inflow of ground water from the upper part of the field resulting in non-uniform water content distribution. Four drainage methods namely Open Ditch, Vinyl Barrier, Pipe Drainage and Tube Bundle for multiple land use were installed within 1-m position from the lower edge of the upper embankment of sloping alluvial paddy fields. This study was conducted to evaluate soil physical characteristics by drainage improvement in poorly drained sloping paddy field. The results showed that subsurface drainage by Pipe Drainage improves the productivity of poorly drained soils by lowering the water table and improving root zone soil layer condition. In an Pipe drainage plot, soil moisture drained faster as compared to the other drainage methods. Infiltration rate showed high tendency to Piper Drainage method about $20.87mm\;hr^{-1}$ than in Open Ditch method $0.15mm\;hr^{-1}$. And Similarly soil water and degree of hardness and shear strength phase of soil profile showed a tendency to decrease. From the above results, we found that when an subsurface drainage was established with at 1m position from the lower edge paddy levee of the upper field in sloping poorly drained paddy fields Pipe Drainage was the most effective drainage system for multiple land use.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.6
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• pp.522-528
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• 2009

This study focused on establishing prediction models using visible-near infrared spectrum to simultaneously detect multiple components of soils and enhancing the performance quality by suitably transformed input spectra and classification of soil spectral types for prediction model input. The continuum-removed spectra showed significant result for all cases in terms of soil properties and classified or bulk predictions. The prediction model using classified soil spectra at an absorption peak area around 500nm and 950nm efficiently indicating soil color showed slightly better performance. Especially, Ca and CEC were well estimated by the classified prediction model at $R^{2}$ > 0.8. For organic carbon, both classified and bulk prediction model had a good performance with $R^{2}$ > 0.8 and RPD> 2. This prediction model may be applied in global soil mapping, soil classification, and remote sensing data analysis.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.3
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• pp.145-151
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• 2009

This study was conducted to develop rational soil management and enhance the productivity of lands converted from paddy soils. Specifically, the changes in the soil physical properties brought about by the change in land usage from paddy soil were evaluated. This was carried out from 1999 to 2001 at 50 site in large-scale converted paddy fields of Kimcheon, Youngcheon, Gyeongsan and Milyang in the Youngnam region, categorized according to soil texture and drainage class. The ridge height of converted paddy soils was higher in coarse-textured and poorly-drained soils than in fine-textured and well-drained soils. The gray color of the surface soil was of lesser degree in converted soils than paddy soils and more notable in welldrained soils. The porosity ratio and the formation of aggregate structure were higher, and the appearance of soil mottling was deeper in converted paddy fields than in paddy soils. The glaying layer "g" of surface soil degraded with time. The porosity and amount of water stable aggregate was found to increase with time after conversion. The penetration resistance of the converted paddy soil was lower and deeper with time after conversion. The soil aeration of the converted paddy soil was lower in sandy loam than in loamy soil. Furthermore, soil aeration was influenced by ridge height and drainage class in poorly-drained soils.