• Korean Journal of Soil Science and Fertilizer
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• v.48 no.2
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• pp.138-145
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• 2015

Heavy metal pollution in agricultural field near the abandoned metal mines is a critical problem in Korea. General remediation technique is to apply chemical amendments and soil covering. However, there is no specific guidelines for conducting soil covering. Therefore, main objective of this research was to determine optimum soil covering technique with microcosm experiment. Three different chemical amendments, lime stone (LS), steel slag (SS), and acid mine drainage sludge (AMDS), were examined and varied soil covering depth, 20, 30, 40cm, was applied to determine optimum remediation technique. Bioavailable heavy metal concentration in soil and total concentration of heavy metals in crop were monitored. Result showed that average heavy metal concentration in varied soil covering depth was ordered as 40 cm ($14.5mg\;kg^{-1}$) < 20 cm ($14.6mg\;kg^{-1}$) < 30 cm ($16.0mg\;kg^{-1}$) and also heavy metal concentration in crop was ordered as 40 cm ($100{\mu}g\;kg^{-1}$) < 30 cm ($183{\mu}g\;kg^{-1}$) < 20 cm ($190{\mu}g\;kg^{-1}$). In terms of chemical amendments, average heavy metal concentration was decreased as AMDS ($150{\mu}g\;kg^{-1}$) < SS ($151{\mu}g\;kg^{-1}$) < LS ($154{\mu}g\;kg^{-1}$). Overall, depth of soil covering should be over 30 cm to minimize bioaccumulation of heavy metals and SS and LS could be applied in heavy metal contaminated soil for remediation purposes.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.1
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• pp.22-29
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• 1991

This study was experimented to obtain the basic information on the changeable aspect and improvement of soil fertility in newly-reclaimed sloped land. Silage corn was cultivated under the six different treatments for 4 years. The relation between the amount or ratio of annual changes of soil physico-chemical properties and yield of silage corn were analyzed. Soil bulk density was decreased in 3rd year at topsoil, but that decreased in 4th year at subsoil. Soil organic matter also decreased in 2nd year at topsoil, and decreased continuously at subsoil. Bulk density and hardness of soil depths showed significant negative simple correlation with dry matter yield and cation exchange capacity showed positive. Correlation coefficient of chemical properties with dry matter yield were low. The range of annual changes of moisture percent, hardness and organic matter were wider than the other properties. The significantly different of physical properties were higher than the chemical properties, and those of topsoil were higher than subsoil. According to multiple regression between yield and physico-chemical properties of subsoil, bulk density and cation exchange capacity were in the greatest contribution at the variations, but bulk density was greatest at the ratios.

• Journal of the Korean Wood Science and Technology
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• v.44 no.2
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• pp.231-240
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• 2016

The change in chemical compositions of leachate and medium density fiberboard (MDF) from a laboratory-scale simulated landfill which constructed in a plastic container containing alternating layers of soil and MDF was investigated to evaluate decomposing of MDF in soil. Four treatments were conducted: 1) MDF in soil, 2) MDF only, 3) cured UF resin in soil, and 4) soil only. Molecular weight (MW) distribution of compounds in leachate from soil only treatment did not change over time. In UF resin in soil treatment, the MW distribution shifted to a lower MW distribution over time, while the peak shifted to the left indicated changing to higher MW distribution in leachate from treatment 1 and 2 contained MDF. Higher percent nitrogen in leachate was observed in MDF containing treatments due to the UF resin in the MDF. The percent carbon slightly increased in MDF only while that greatly decreased in MDF in soil treatment maybe due to bacterial activity. The percent of extractable materials from the MDF decreased greatly on day 35 compare to day 0, and subsequently did not change much on day 77. In contrast, percent holocellulose and lignin did not change much over time. No structural change of the wood fiber in MDF occurs during the study. Water-soluble materials from MDF in soil contributed the change in chemical composition of leachate.

• Geotechnical Engineering
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• v.4 no.4
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• pp.29-38
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• 1988

One of the main objectives of researches for the chemical grouting is to assess the changes in soil properties caused by injection of chemical grout. Especially the changes in the strength properties of soils, such as elastic modulus, shear modulus of ground due to injection of chemical grout has drawn our attention. Since the specific surface changes with variation in the grain size of sandy soil, the influence of grain size of sandy toil on the strength and stiffness of silicate-grouted soil was investicated in this study by earring out uniaxial and triaxial compression tests. It was found that the strength and stiffness of grouted soil increased as the grain size of sandy soil decreases, the possibility of estimating the strength of grouted soil was confirmed through the study of relationship between specific surface of sandy soil and the strength of chemical gel.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.189-196
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• 2003

Soil-cement column is often used as a contaminant barrier. This study presents the results of experimental study performed to investigate the changes of properties of soil-cement column under the attack of acids. Sulfuric nitric, and ascetic acid were used as contaminants. Specimen were made of clayey and sandy soils with addition of cement and water Permeability of soil-cement decreased with time during permeability test. When significant amount of acid percolated the specimen, permeability increased and compressive strength decreased due to the dissolution and leaching of cement and its chemical reaction compounds. Sulfuric and nitric acid were more effective than ascetic acid in deteriorating soil-cement column. Amount of acid required to lower the pH of soil cement below 12 was calculated from the results of permeability tests. This leads to a conclusion that, under the conditions employed in this study, the chemical stability of soil-cement column could be maintained against acid attack for longer than generally accepted lifetime of contaminant barriers.

• Journal of Soil and Groundwater Environment
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• v.13 no.6
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• pp.62-71
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• 2008

Soil quality standards (SQS) are necessary to protect the human health and soil biota from the exposure to soil pollutants. The current SQS in Korea contain only sixteen substances, and it is scheduled to expand the number of substances. Chemical ranking and scoring (CRS) system is very effective to screen the priority chemicals for the future SQS in terms of their toxicity and exposure potential. In this study, several CRS systems were extensively compared to propose the assessment factors that required for the screening of soil pollutants The CRS systems considered in this study include the CHEMS-1 (Chemical Hazard Evaluation for Management Strategies), SCRAM (Scoring and Ranking Assessment Model), EURAM (European Union Risk Ranking Method), ARET (Accelerated Reduction/Elimination of Toxics), CRSKorea, and other systems. The additional assessment factors of CRS suitable for soil pollutants were suggested. We suggest soil adsorption factor as an appropriate factor of CRS system to consider chemical transport from soil to groundwater. Other factors such as soil emission rate and cases of accident of soil pollutants were included. These results were reflected to screen the priority chemicals in Korea, as a part of the project entitled ‘Setting the Priority of Soil Contaminants'.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.5
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• pp.572-576
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• 2016

Soil quality assessment is an important tool for environmental management in an agricultural field. It can be used to evaluate the health of the soils and to establish the basis for sustainable urban agriculture and soil management. For this study, the chemical properties of the soils used for urban agriculture were examined. Results of the soil analysis for chemical properties were applied to soil quality assessment system, which is composed of principal component analysis, application to scoring function and derivation of soil quality index (SQI). Soil pH, electrical conductivity (EC), organic matter (OM), total nitrogen (T-N) were determined for minimum data set (MDS) according to principal component analysis. Based on the results of scoring for four indicators (pH, EC, OM, T-N), soil pH was the indicator that needs the most urgent management. Results of SQI derivation showed that many of the urban farms appeared to be insufficient score in comprehensive soil quality assessment. In conclusion, soil management practices based on scores derived from soil chemical indicators need to be carried out to maintain sustainable urban agricultural soil environment and to provide easy-to-understand information to urban farmers.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1130-1136
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• 2011

This study was carried out to determine the effects of pig slurry on growth of potato (Solanum tuberosum L. cv. Dejima), soil chemistry properties and infiltration water quality in volcanic ash soil and non-volcanic ash soil of Jeju. Fertilization of liquid pig manure was based on nitrogen. In volcanic ash soil and non-volcanic ash soil, there was no difference in the height and diameter of stems in chemical fertilizer and liquid pig manure application treatments. Also yields of potatoes were no significantly difference in chemical fertilizer and liquid pig manure application treatments. pH in all soil was increased by application of liquid pig manure compared to the chemical fertilizer plot. Contents of exchangeable K in all soil were accumulated excessively by fertilization of pig manure 100% compared to the chemical fertilizer 100%. But there was no difference between the chemical fertilizer 50%+liquid pig manure 50% and chemical fertilizer 100%. No difference between the chemical fertilizer and liquid pig manure was observed in available phosphate, exchangeable Ca and Mg. $NO_3$-N concentration of infiltration water sample collected at 70cm of soil depth was lower non-fertilizer than chemical fertilizer and liquid pig manure application treatments. In volcanic ash soil, the $NO_3$-N concentration of infiltration water was decreased from early, except liquid manure 100%. In non volcanic ash soil, the $NO_3$-N concentration of infiltration water increased until October 8, but then was reduced. In all soils, $NO_3$-N concentration of infiltration water was higher in the liquid manure 100% than those in the chemical fertilizer 100% and chemical fertilizer 50%+liquid pig manure 50%, but there were no differences. In conclusion, the growth of potato, fertilization of soil and $NO_3$-N content of infiltration water were not different between chemical 50%+liquid pig manure 50% and chemical 100% plot. So, liquid pig manure could be substituted for some amount of chemical fertilizer.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.500-505
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• 2014

In recent years, organic ginseng cultivation has increased because customers prefer organic ginseng products due to the morphological quality as well as the safety such as the residuals of chemically-synthesized pesticides. Therefore, some of paddy and upland fields were converted into organic ginseng fields. Soil chemical properties, soil microflora, and soil-inhabiting animals were investigated in paddy-converted and upland organic ginseng fields in Sangju city, Korea. There was few difference in the soil chemical properties, and the soil nutrient concentrations, such as nitrate-N, Av. $P_2O_5$ between the two field types, and exchangeable cations such as K and Ca were within the ranges which are recommended by the standard ginseng-farming manual. Changes in microflora were also assessed by analyzing phospholipid fatty acid composition. Overall, indicators of microbial groups were greater in the upland field than in the paddy-converted soil, but they were not significantly different. In addition, there was no significant change in the abundance of nematodes, collembolans, and mites between the two field types probably because of the high variation within the field types. In this study, it was suggested that soil chemical and biological properties for organic ginseng cultivation were greatly influenced by the variation of topography and soil management practices rather than field types. Further study may be needed to investigate the influence of these factors on soil chemical and biological properties in organic ginseng soils.

• 한국환경농학회:학술대회논문집
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• 2009.07a
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• pp.93-115
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• 2009

There are growing public concerns over crop and food safeties due to the elevated levels of heavy metals grown in contaminated soil. Heavy metals are classified as the chemical harmful risks for crop and food safety. With implementation of GAP, crop safety is controlled by many regulatory options for soil, irrigation water and fertilizers. Any attempt to retard the metal uptake by crops may be the best protocol to secure crop and food safety. This article reviews the management strategies for heavy metals in view of crop safety in Korea and demonstrates results from the field experiments to retard metal translocation from soil to crops by using chemical amendments and soil layer management methods. Major source of soil pollution by heavy metals has been related with mining activities. Risk assessment revealed that rice consumption and groundwater ingestion in the abandoned mining areas were the major exposure pathways for metals to human and the heavy metal showed the toxic effects on human health. Chemical amendments such as lime and slag retarded Cd uptake by rice (Oryza sativa L.) by increasing soil pH, lowering the phytoavailable Cd concentration in soil solution, immobilizing Cd in soil and converting the available Cd fractions into non-available fractions. The soil layer management methods decreased the Cd uptake by 76% and Pb by 60%. Either reversing the surface layer with subsurface layer or immobilization of metals with layer mixing with lime was considered to be the practical option for the in-situ remediation of the contaminated paddy soils. Combination of chemical soil amendments and layer management methods was efficient to retard the metal bioavailability and thus to secure crop safety for heavy metals. This protocol seems to be cheap, relatively easy to practice and practical in the agricultural fields. However, a long term monitoring work should be followed to verify the efficiency of this protocol.