• Korean Journal of Soil Science and Fertilizer
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• v.42 no.2
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• pp.132-138
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• 2009

Soils originated from limestone, located at the southern part of Kangwon province and Jecheon, Danyang of Chungbuk province are mainly composed of fine texture, have different properties from soils originated from granite and granite gneiss, especially for water movement. This study was conducted for making PTF(Pedo-Transfer Function) for Kfs(field saturaton hydraulic conductivity) estimation, and for investigating the relation between soil particle distribution and the infiltration and percolation rate in soils originated from limestone. Soils used for the experiment were 6 soils of Gwarim, Mosan, Jangseong, Maji, Anmi and Pyongan series. Infiltration and percolation rate for the soil were measured by a disc tension infiltrometer and a Guelph permeameter, respectively. The particle size distribution and organic matter content of the soils were analyzed. Kfs was not related with sand, silt, clay, and organic mattrer (OM) content because of forest soils which contained high gravel, pebble, and cobble content, and O layer with high OM content. After Mosan soil series and O layer of Gwarim series were excluded for the data analysis, Kfs was explained as a linear function with sand and clay content and a exponential function with OM content. As a result, the PTF equation was obtained as Kfs=-4.20558+0.479706*(S)+0.023187*exp(1.829*OM) ($R^2=0.6558^{*}$).

• Korean Journal of Soil Science and Fertilizer
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• v.6 no.1
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• pp.35-52
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• 1973

Red Yellow Soils occur very commonly in Korea and constitute the important upland soils of the country which are either presently being cultivated or are suitable for reclaiming and cultivating. These soils are distributed on rolling, moutain foot slopes, and terraces in the southern and western parts of the central districts of Korea, and are derived from granite, granite gneiss, old alluvium and locally from limestone and shale. This report is a summary of the morphology, physical and chemical characteristics of Red Yellow Soils. The data obtained from detailed soil surveys since 1964 are summarized as follows. 1. Red-Yellows Soils have an A, Bt, C profile. The A horizon is dark colored coarse loamy or fine loamy with the thin layer of organic matter. The B horizon is dominantly strong brown, reddish brown or yellowish red, clayey or fine loamy with clay cutans on the soil peds. The C horizon varies with parent materials, and is coarser texture and has a less developed structure than the Bt horizon. Soil depth, varied with relief and parent materials, is predominantly around 100cm. 2. In the physical characteristics, the clay content of surface soil is 18 to 35 percent, and of subsoil is 30 to 90 percent nearly two times higher than the surface soil. Bulk density is 1.2 to 1.3 in the surface soil and 1.3 to 1.5 in the subsoil. The range of 3-phase is mostly narrow with 45 to 50 percent in solid phase, 30 to 45 percent in liquid one, and 5 to 25 percent in gaseous state in the surface soil; and 50 to 60 solid, 35 to 45 percent liquid and less than 15 percent gaseous in the subsoil. Available soil moisture capacity ranges from 10 to 23 percent in the surface soil, and 5 to 16 percent in the subsoil. 3. Chemically, soil reaction is neutral to alkaline in soils derived from limestone or old fluviomarine deposits, and acid to strong acid in other ones. The organic matter content of surface soil varying considerably with vegetation, erosion and cultivation, ranges from 1.0 to 5.0 percent. The cation exchange capacity is 5 to 40 me/100gr soil and closely related to the content of organic matter, clay and silt. Base saturation is low, on the whole, due to the leaching of extractable cations, but is high in soils derived from limestone with high content of lime and magnesium. 4. Most of these soils mainly contain halloysite (a part of kaolin minerals), vermiculite (weathered mica), and illite, including small amount of chlorite, gibbsite, hematite, quartz and feldspar. 5. Characteristically they are similar to Red Yellow Podzolic Soils and a part of Reddish Brown Lateritic Soils of the United States, and Red Yellow Soils of Japan. According to USDA 7th Approximation, they can be classified as Udu Its or Udalfs, and in FAO classification system to Acrisols, Luvisols, and Nitosols.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.1
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• pp.64-71
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• 2015

Soil contamination with arsenic and heavy metals is a worldwide problem. Main objective of this research was to evaluated effects of reducing heavy metal leaching under reduced soil condition amended with industrial by-products. The contaminated soil was amended with 3% (w/w) of limestone (Ls), steel slag (SS) and acid mine drainage sludge (AMDS). Synthetic acid rain ($H_2SO_4:HNO_3=6:4$, pH 5.5 fixed) was used for feeding solution with flow rate of $0.78{\sim}0.88mL\;min^{-1}$. Results showed that similar pH and EC of leachate was observed in all treatments regardless of applied industrial by-products. However, arsenic concentration of leachate increased when industrial by-products were mixed. Meanwhile, concentration of heavy metal in the leachate decreased from 11.3 to 4.59 mg for Cd, from 92.3 to 7.93 mg for Pb, and from 11,716 to 1,788 mg for Zn via immobilization in soil with AMDS amended, respectively. Overall, application of industrial by-products can be an environmentally-friendly way to remediate soil and(or) leachate contaminated with metal(loid)s in metal mine site.

• The Journal of Engineering Geology
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• v.33 no.3
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• pp.427-438
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• 2023

We carried out a geological survey to classify the types of mass movement in Danyang Geopark (where various rock types are distributed) and analyzed the mechanical and hydraulic characteristics of landslide materials using a series of laboratory tests. Debris flows occurred in areas of limestone/marble, shale, and porphyroblastic gneiss, and limestone/marble landslides were distinguished from the others through the presence of karren topography. Soil tests showed that soil derived from weathered gneiss, which has a higher proportion of coarse grains, has a higher friction angle, lower cohesion, and larger hydraulic conductivity than soils from areas of limestone/marble, and shale. Rock failure mass movements occurred in areas of phyllite, sandstone, and conglomerate and were subdivided into plane failure, block-fall, and boulder-fall types in areas of phyllite, sandstone, and conglomerate, respectively. The shear strength of phyllite is much lower than that of the other types of rock, which have similar rock quality. The slake durability index of the conglomerate is similar to that of the other rock types, which have similar degrees of weathering, but differential weathering of the matrix and clasts was clearly observed when comparing the samples before and after the test. This study can help establish appropriate reinforcement and disaster prevention measures, which depend on the type of mass movement expected given the geological characteristics of an area.

• Journal of Soil and Groundwater Environment
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• v.26 no.1
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• pp.8-16
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• 2021

This study has evaluated the stabilization of As contaminated paddy and cultivated soils by pot experiments for rice and lettuce. Various ratios of limestone (L) and steel slag (S) were mixed with the soils in each pot. The soils were taken from before and after pot experiments, and analyzed for As extracted by sequentially (Wenzel method) and totally (aqua regia method).. Paddy soils amended with L (0.5%) and L (1.0%) + S (1.0%) showed increasing fraction 2 (specifically bound As) compared with control soil. Arsenic concentrations in rice grain grown on the amended soils decreased 14% and 12% compared with those on the control soil, respectively. According to sequential extraction of As in cultivated soils, the fractions 1~3 were decreased due to stabilization of As by the soil amendment, especially for S (1.0%), S (3.0%) and L (1.0%) + S (1.0%). In addition, relatively low As concentrations were found in lettuce grown on amended soils with L (0.5%) and L (1.0%) + S (1.0%). Therefore, it can be suggested that soil amendments with L (0.5%) or L (1.0%) + S (1.0%) were suitable for enhancing stabilization of As in the study area.

• The Journal of Engineering Geology
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• v.1 no.1
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• pp.2-10
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• 1991

Some geotechnical considerations might be suggested to the construction performance from the school and the housing projects in Tripoli sub-region, Libya. The subsurface informations were compiled from the site investigation reports, for which more than 700 borings and lots of laboratory test had been conducted from 1984 to 1986. Most subsurface of 10 meter depth in the Jafara plain consists of medium dense silty sand. Some ground in the plain have poor top soil with interbedded calcarenite or limestone. The shallow subsurface is found to be very poor soil in the southern mountain range. Weak soil is hardly found except in the sabkha area. In general, natural silty sand layer may have a presumed bearing capacity of more than 150kN/$m^2$, where spread or strip footing is applied. Proper fine aggregate and natural coarse one are restricted in Tripoli sub-region. Coarse aggregate is generally supplied from the dolomite quarry.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.4
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• pp.414-419
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• 1998

The contribution of soil organic matter on the soil surface charge characteristic of paddy and upland soils weathered from granite or limestone was evaluated. The surface charge characteristics of the soils with and without soil organic matter by pre-treatment with hydrogen peroxide was determined at pH 3.5~9.0 range using the ion adsorption method. Regardless of soil organic matter removal, the soil surface negative charge increased linearly by the increase of pH with high statistical significance at all kinds of soils. Here, the differential increasement of soil surface negative charge by pH inclease, dCEC/dpH, was proposed as the parameter of pH dependency of the soil surface charge. The dCEC/dpH of soils with organic matter was in the range of 0.91~4.59, while it was dramatically decreased to the range 0.16~1.91 by the removal of organic matter. The soil surface charge derived from soil organic matter ranged from 15% to 82% to the total amount of surface charge. The magnitude of surface charge carried by 1% of soil organic matter showed considerable differences between soils from 0.22 to $5.03cmol^+\;kg^{-1}$. The effect of soil organic matte on the dCEC/dpH was higher in paddy soils with high oxalic acid extractable Fe than upland soils.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.2
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• pp.73-80
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• 2013

Due to the fact that possible risk associated with soil-crop-food chain transfer, metal contamination in croplands has become a major topic of wide concern. Accumulation of toxic metals in edible parts of crops grown in contaminated soils has been reported from number of crops including rice, soybean, wheat, maize, and vegetables. Therefore, in order to ensure food safety, measures are needed to be taken in mitigating metal pollution and subsequent uptake by crop plants. Present paper critically reviewed some of the cost effective remediation techniques used in minimizing metal uptake by crops grown in contaminated soils. Liming with different materials such as limestone ($CaCO_3$), burnt lime (CaO), slaked lime [$Ca(OH)_2$], dolomite [$CaMg(CO_3)_2$], and slag ($CaSiO_3$) has been widely used because they could elevate soil pH rendering metals less-bioavailable for plant uptake. Zn fertilization, use of organic amendments, crop rotation and water management are among the other techniques successfully employed in reducing metal uptake by crop plants. However, irrespectively the mitigating measure used, heterogeneous accumulation of metals in different crop species is often reported. The inconsistency might be attributed to the genetic makeup of the crops for selective uptake, their morphological characteristics, position of edible parts on the plants in respect of their distance from roots, crop management practices, the season and to the soil characteristics. However, a sound conclusion in this regard can only be made when more scientific evidence is available on case-specific researches, in particular from long-term field trials which included risks and benefits analysis also for various remediation practices.

• Korean Journal of Agricultural Science
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• v.46 no.1
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• pp.205-217
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• 2019

The aim of this study was to identify land resources because food production and supply in North Korea have been at risk due to variations in its seasonal climate. More than three-fifths of the soils are locally derived from the weathering of granitic rocks or various kinds of schists developed from crystalline rocks. Well-developed reddish brown soils derived from limestone are found in the North Hwanghae province and in the southern part of the South Pyeongan province. Additionally, a narrow strip of similarly fertile land runs through the eastern seaboard of the Hamgyong and Kangwon Provinces. The loss of clay particles and organic matter are major causes of degradation in the soil physical and chemical properties in North Korea. 75% of the areas converted from forests became croplands, and 69% of the land converted to croplands came from forests. The net forest loss was quite small from the 1990s to the 2000s. However, deforestation in areas with a slightly lower elevation and gentler slope between 1997 and 2014 led to severe soil erosion resulting in a drastic change in the physical and chemical properties of the soil which influenced cropland stability and productivity. Therefore, the drastic changes in land cover as well as in the physical and chemical properties of the soil caused by various geographical features have seriously influenced the productivity of crops in North Korea.

• Economic and Environmental Geology
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• v.57 no.4
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• pp.417-429
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• 2024

To assess the effectiveness of stabilization techniques on the transfer of As and heavy metals in soil to rice plant, pot experiments were conducted using organic (biochar), inorganic (limestone-steel slag mixture), and microbiological (sulfate-reducing bacteria, SRB) stabilizers. The results showed that microbiological treatments, particularly when SRB and SO₄^2- were co-injected, achieved higher stabilization efficiencies for Pb, Cu, and Cd in soil solution by the end of the experiments (153 days). The transfer of Pb, Zn, Cu, and Cd to the rice stems, leaves, and husks was reduced across all stabilization treatments. Notably, in husks, the stabilization efficiencies of Pb, Zn, Cu, and Cd ranged from 30% to 65% for organic stabilizers and 23% to 69% for inorganic stabilizers, surpassing those achieved with microbiological stabilizers. This study highlighted the potential of SRB as an effective alternative or supplementary stabilizer to conventional options such as limestone, steel slag, and biochar in reducing the transfer of heavy metals to crops in paddy soils.