• Korean Journal of Soil Science and Fertilizer
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• v.25 no.4
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• pp.311-324
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• 1992

Polymeric substances in organic matter of soils aggregate soil particles into a crumb structure which greatly influences such properties as water movement, aeration and heat transfer. Poorly-structured soils may be improved by the incorporation of synthetic polymers where the main objects are : promoting germination or establishing crops, improving drainage, combating wind and water erosion, and reducing evaporation from the surface of soil under arid condition.

• Journal of Microbiology
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• v.41 no.2
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• pp.169-173
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• 2003

A treatability investigation was conducted to determine if landfarming would be effective for the remediation of unsanitary landfill waste soils. Calculations based on biodegradable organic carbon contents and initial CO$_2$ evolution rates revealed that landfarming has a high potential for landfill site remediation and that the optimum strategy for bioremediation is site-specific.

• Journal of the Korean Geotechnical Society
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• v.40 no.3
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• pp.93-100
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• 2024

Pore water freezes in low-temperature compaction, which leads to different compaction characteristics compared to room temperature conditions. In regions like Alberta, Canada, where organic soils are prevalent, compaction performance is influenced by the high water retention and compressibility of organic soils, as well as their sensitivity to freezing and thawing. Alberta's strict environmental regulations demand the reuse of excavated soil for backfill, and the long winter season creates challenging conditions for civil engineering projects. In this study, a laboratory compaction test was conducted to evaluate the low-temperature compaction characteristics of organic soils with varying organic content. The results indicate that the optimum moisture content increases as the organic content increases, and the maximum dry unit weight decreases by up to 21.9%. In addition, under temperature conditions below -4℃, no optimum moisture content was observed, and the dry unit weight decreased as the moisture content increased.

• Journal of The Korean Society of Agricultural Engineers
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• v.61 no.6
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• pp.1-8
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• 2019

Carbon dioxide is one of the major driving forces causing climate changes, and many countries have been trying to reduce carbon dioxide emissions from various sources. Soil stores more carbon dioxide(two to three times) amounts than atmosphere indicating that soil organic carbon emission management are a pivotal issue. In this study, we developed a Soil Organic Carbon(SOC) storage estimation model to predict SOC storage amounts in soils. Also, SOC storage values were assessed based on the carbon emission price provided from Republic Of Korea(ROK). Here, the SOC model calculated the soil hydraulic properties based on the soil physical and chemical information. Base on the calculated the soil hydraulic properties and the soil physical chemical information, SOC storage amounts were estimated. In validation, the estimated SOC storage amounts were 486,696 tons($3.526kg/m^2$) in Jindo-gun and shown similarly compared to the previous literature review. These results supported the robustness of our SOC model in estimating SOC storage amounts. The total SOC storage amount in ROK was 305 Mt, and the SOC amount at Gyeongsangbuk-do were relatively higher than other regions. But the SOC storage amount(per unit) was highest in Jeju island indicating that volcanic ashes might influence on the relatively higher SOC amount. Based on these results, the SOC storage value was shown as 8.4 trillion won in ROK. Even though our SOC model was not fully validated due to lacks of measured SOC data, our approach can be useful for policy-makers in reducing soil organic carbon emission from soils against climate changes.

• Korean Journal of Environmental Agriculture
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• v.10 no.2
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• pp.119-127
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• 1991

In order to reveal the mechanism of heavy metal behavior in soils relating to factors such as soil pH, organic matter, C.E.C. and soil minerals influencing the activities of heavy metals, Cd, Cu and Zn were applied to soil columns filled with 8 different soils with adjusted soil pH to several levels between 3.0 to 11.0 and the amounts of adsorption and desorption of these heavy metals were measured. 1. At the adsorption maxima of three heavy metals(Cd, Cu and Zn) soil pH appeared to be near 6.0 regardless of properties of the 8 soils, and adsorption gradually decreased above and below pH 6.0. This phenomenon was the same in both heavy metal solutions and mixed solutions, and the mixed solution, containing three heavy metals, revealed slightly higher amounts of Cu adsorption and Cd adsorption. 2. It was also found that the adsorption of Cu and Zn by soils was positively correlated with C.E.C. and the organic matter of soils, respectively. However, the pH values showing maxima of heavy metal adsorption were negatively correlated with organic matter content by contrast with the correlation between the maxima and the C.E.C. values in soils. 3. The adsorption of Cu by soils markedly increased more with $Ca(OH)_2$ application than with NaOH application for soil pH adjusment. This was probably because of Ca effects in Cu precipitation in soils, in addition to the effect of the simple soil pH itself on Cu adsorption 4. It was also revealed that adsorbed Cu was hardly desorbed by $N-NH_4OAC$ solution from the Daejeong soil series compared to the Jeonbug and Yechun soil series. This was because the Daejeong soil series consisted of large amounts of expanding type Vermiculite minerals and also was high in C.E.C. and soil organic matter.

• Applied Biological Chemistry
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• v.28 no.2
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• pp.68-75
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• 1985

Laboratory experiments were conducted to investigate the effect of compost and humic acid treatment on adsorption of Cd, Zn, and Cu in soils. Three soils differing in physical and chemical properties used in this experiments were Bonyrang (Typic Udifluvents) SL, Gangseo (Aquatic Eutrochrepts) L, and Gyorae (Typic Distrandepts) SiL. Adsorption of Cd, Zn, ana Cu on the soils followed Langmuir isotherm up to 75 ppm of initial concentration. The adsorption maxima of Cd, Zn, and Cu for the Bonryang soil, the lowest in pH, organic matter content, and CEC, were the lowest of the three soils. Although the Gyorae soil derived from volcanic ash was the highest in organic matter content and CEC, the adsorption maxima of heavy metals for the Gyorae soil were lower than those for the Gangseo soil of which organic content and CEC were intermidiate. The adsorption maxima/CEC ratios for the Bonryang, the Gangseo, the Gyorae soils were found to be in the range of $23{\sim}27%,\;28{\sim}57%$, and $11{\sim}14%$ respectively The bonding energy constants of Cd, Zn, and Cu for the soils were in the order of Gangseo>Bonryang>Gyorae soils. The adsorption maxima of Cd, Zu, and Cu for the Bonryang soil increased with compost treatment by $100{\sim}210%,\;90{\sim}230%$, and $130{\sim}290%$ respectively, while little difference was observed when the soil was treated with humic acid Bonding energy constants of Cd, Zn, and Cu for the Bonryang soil increased significantly with compost treatment, and showed insignificant correlation with humic acid treatment.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.3
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• pp.239-244
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• 1986

This study was conducted to investigate the characteristics of humic substances and the fractional distribution of organic nitrogen in Korean paddy soils. The results are obtained as follows: 1. The content of humus in soils used was 665-2680 mg/100g and the average contents of humic acid in normal paddy soils and in sandy paddy soils were 1436 mg/100g, 970 mg/100g respectively. 2. The humic acid diagrams classed by Kumada method belong to B type, P type and Rp type. 3. The content of Mineral - N to Total - N was 1.04-2.86% and the average contents of that in sandy paddy soils and in normal paddy soils were 1.72% and 1.75% respectively. 4. The fractionations of acid hydrolysable organic - N in sandy paddy soils were Amino acid - N (31.52%), Humin - N (20.63%), Amino sugar - N (18.70%), and Unknown - N (25.73%).

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.5
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• pp.732-739
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• 2009

Pig slurry is a good soil amendment not only because of its high organic matter content, but also because of its ability to provide various nutrients. The objective of this study was to estimate the influence of raw and processed pig slurry application on pot soil over chemical fertilizer and non-amended control soil. Change in the chemical parameters (pH, organic matter (OM), organic carbon (OC), macro and micronutrients) and microbial mass of the treated soils were monitored over 30 to 90 days. Pot soil was treated with the recommended dose of pig slurry and chemical fertilizer, and was sampled after 30, 60 and 90 days of incubation. The least significanct difference (p<0.05) was observed on Fe, Cu, Zn, available P and K between treatments. All treatments increased N, P and K content and microbial mass of soil over control soil. Interestingly, no significant effects were detected on OM, OC, total bacteria, actinomycetes and fungi mass in soil irrespective of treatments given. However fungal and bacterial counts, as well as available nutrients, were found to be higher in processed slurry (PS)-treated soil compared to other soils. In general a significant correlation existed between the fungal count and OM, OC, Zn, T Kjeldahl N (TKN), available P and K of soil. A strong negative correlation was observed between pH and Fe in soil. This study clearly demonstrated that the use of processed manure as a fertilizer could be a key for sustainable livestock agriculture.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1098-1108
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• 2008

Batch type and column type experiments were performed in order to predict adsorption and movement within soil. Clay minerals montmorillonite and kaolinite were respectively added to paraquat which is a cationic compound with long residual time, 2,4-D which is an anionic compound with relatively short residual time and napropamide which is an amphoteric compound. Therefore, it is very important to determine the movements of toxic pollutants in the ground soil to establish measures to prevent soil grounds contamination and to restore contaminated soils effectively, because contamination of soil is getting severe due to these toxic wastes, industrial waste water, and agricultural chemicals, etc. Therefore, in this study, we have carried out column and batch experiments by using general toxic organic compounds as test samples in order to restore contaminated soils effectively as well as to prepare a basic data to develop absorbents that will remove various toxic organic compounds, with a grandiose purpose to prevent contaminations of soil and grounds due to various toxic organic compounds.

• Geomechanics and Engineering
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• v.38 no.2
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• pp.191-203
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• 2024

One of the issues with clayey soils, particularly those with significant quantities of organic matter, is the creep settling problem. Clay soils can be strengthened using a variety of techniques, one of which is the use of stone columns. Prior research involved foundation loading when the soil beds were ready and confined in one-dimensional consolidation chambers. In this study, a particular methodology is used to get around the model's frictional resistance issue. Initially, specimens were prepared via static compaction, and they were then re-consolidated inside a sizable triaxial cell while under isotropic pressure. With this configuration, the confining pressure can be adjusted, the pore water pressure beneath the foundation can be measured, and the spacemen's lateral border may be freely moved. This paper's important conclusions include the observation that secondary settlement declines with area replacement ratio. Because of the composite ground's increasing stiffness, the length to diameter ratio (l/d) and the stone column to sample height ratio (Hc/Hs) both increase. The degree of improvement varies from 12.4 to 55% according to area replacement ratio and (l/d) ratio.