• The Plant Pathology Journal
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• v.16 no.5
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• pp.283-285
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• 2000

Two field tests were conducted in 1995 to examine the effects of composts and soil amendments on physicochemical properties of soil in relation to Phytophthora root and crown rot of bell pepper. Chitosan, crab shell waste, humate, sewage sludge-yard trimmings, and wood chips were applied to test plots, some of which affected the levels of P, K, Mg, pH, and H. Physicochemical properties were not related with disease incidence, but percent organic matter, estimated nitrogen release, K, and Mg were correlated with total microbial activity. The elements K and Mg were especially responsible for the increased soil microbial activity that could affect development of root and crown rot of pepper.

• Journal of Soil and Groundwater Environment
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• v.17 no.4
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• pp.36-43
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• 2012

Various methods are used to remediate soil contaminated with heavy metals or petroleum. In recent years, harsh physical and chemical remediation methods are being used to increase remediation efficiency, however, such processes could affect soil properties and degrade the ecological functions of the soil. Effects of soil washing, thermal desorption, and land farming, which are the most frequently used remediation methods, on the physicochemical properties of remediated soil were investigated in this study. For soils smaller than 2 mm, the soil texture were changed from sandy clay loam to sandy loam because of the decrease in the clay content after soil washing, and from loamy sand to sandy loam because of the decrease in the sand content and increase in silt content during thermal desorption, however, the soil texture remained unchanged after land farming process. The water-holding capacity, organic matter content, and total nitrogen concentration of the tested soil decreased after soil washing. A change in soil color and an increase in the available phosphate concentration were observed after thermal desorption. Exchangeable cations, total nitrogen, and available phosphate concentration were found to decrease after land farming; these components were probably used by microorganisms during as well as after the land farming process because microbial processes remain active even after land farming. A study of these changes can provide information useful for the reuse of remediated soil. However, it is insufficient to assess only soil physicochemical properties from the viewpoint of the reuse of remediated soil. Potential risks and ecological functions of remediated soil should also be considered to realize sustainable soil use.

• Economic and Environmental Geology
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• v.54 no.2
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• pp.259-269
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• 2021

The effects of the physicochemical properties of soil such as soil pH, cation exchange capacity, and organic matter content on single extraction of Cd, Cr, Cu, Ni, Pb, and Zn using CaCl2, HOAc, HNO3, and DTPA were statistically investigated for 69 agricultural soils in Korea. Correlation analysis and multiple regression analysis were applied for soil samples which were grouped on the basis of average values of the physicochemical properties of the soil. Diluted HNO3 extracted higher concentrations of Cr, Cu, Ni, and Pb when compared with the other extractants, however, similar amounts of Cd and Zn were extracted by HOAc with HNO3. The results of correlation analysis indicated that DTPA extraction showed a high correlation with other single and pseudo-total extraction methods, and the physicochemical properties of soil influenced the concentrations of heavy metals leached by the single extraction methods. In the case of Zn, high correlations between pseudo-total and the studied single extraction methods were observed. As a result of regression analysis, it was found that the physicochemical properties of the soil could explain up to 74% of variances of the single extraction results. These results indicate that the physicochemical properties of the soil can have a direct influence on the concentrations of heavy metals extracted by the single extraction methods.

• Journal of Soil and Groundwater Environment
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• v.24 no.2
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• pp.8-22
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• 2019

Among numerous chemicals used globally, the number of emerging contaminants is increasing. Numerical modeling for contaminant fate and transport in the subsurface is critical to evaluate environmental and health risk. In general, such models require physicochemical properties of contaminants as input values, which can be found in numerous chemical databases (DB). However, there exist lack of information specific to recently emerging contaminants, which requires estimation of physicochemical properties using regression programs. The purpose of the study is to introduce the workflow for identifying physicochemical properties of potential contaminants utilizing numerous chemical DBs, which frequently lists up potential contaminants for estimating chemical behavior. In this review paper, details of several chemical DBs such as KISChem, TOXNET, etc. and regression programs including EPI $Suite^{TM}$, ChemAxon, etc. were summarized and also benefit of using such DBs were explained. Finally, a few examples were introduced to estimate predominant phase, removal ratio, partitioning, and eco-toxicities by searching or regressing physicochemical properties.

• Journal of Soil and Groundwater Environment
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• v.16 no.1
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• pp.51-61
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• 2011

Germination tests were conducted to determine the practical concentration levels at which plants can reproduce naturally during the phytoremediation of soils contaminated with a high concentration of petroleum hydrocarbons and heavy metals. The effects of humic acids on plant growth and soil physicochemical properties were also investigated. The results show that phytoremediation can be applied in soils contaminated by multiple contaminants at the former soil contamination potential level of Korean soil quality standards considering successful natural reproduction. It was observed that germination rates of Helianthus annuus and Festuca arundinacea were high after all treatments, and transplantation was more appropriate for Phragmites communis in phytoremediation. Humic acids had a positive effect on the growth of both aboveground and belowground biomass of herbaceous plants. Growth inhibition by multiple contaminants is more severe in the case of aboveground biomass. Germination and growth tests suggest that Helianthus annuus is a suitable phytoremediation plant for soils contaminated with a high concentration of petroleum hydrocarbons and heavy metals. The addition of humic acids also caused changes in the physicochemical properties of contaminated soils. An increase in the carbon and nitrogen content due to the addition of humic acids and a correlation between cation exchange capacity(CEC) and the organic matter content were observed.

• Journal of the Korean Wood Science and Technology
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• v.46 no.6
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• pp.645-655
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• 2018

The use of wood waste as substrate for plant growth exemplifies a strategy for turning waste into resources. The overall objective of this research was to evaluate the effects of wood-based growing media on plant cover in a slope area. Moreover, we tried to find out what physicochemical properties affect plant cover on a slope. For treatments, we tested natural soil, soil mixed with wood-based growing medium (1:1, w/w), and wood-based growing medium by itself. Physical and chemical characteristics were evaluated after four months from the date of treatment application to the experimental slope site. Soil coverage with seedlings of Lespedeza cyrtobotrya was measured for plant growth evaluation. Physicochemical properties were altered by mixing the natural soil with wood-based growing medium. Particularly, soil moisture and organic matter contents were significantly changed in soils treated with wood-based growing medium compared to soil alone. We confirmed that plant coverage rate was high when wood-based growing medium was mixed with the natural soil. There was a significant linear relationship between moisture content and CEC (Cation Exchange Capacity) of all growth media tested and plant coverage. This result was expected, as moisture content tends to increase with organic matter content, such as in wood-based growing medium. In conclusion, the high moisture content of the wood-based growing medium was considered effective for plant growth in the experimental slope site, and this wood-based growing medium provides a means to improve the harmony between the slope and the surrounding environment.

• Journal of Microbiology and Biotechnology
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• v.32 no.5
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• pp.564-574
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• 2022

Microbial diversity in the soil is responsive to changes in soil composition. However, the impact of soil amendments on the diversity and structure of rare and abundant sub-communities in agricultural systems is poorly understood. We investigated the effects of different Chinese herb residue (CHR) soil amendments and cropping systems on bacterial rare and abundant sub-communities. Our results showed that the bacterial diversity and structure of these sub-communities in soil had a specific distribution under the application of different soil amendments. The CHR soil amendments with high nitrogen and organic matter additives significantly increased the relative abundance and stability of rare taxa, which increased the structural and functional redundancy of soil bacterial communities. Rare and abundant sub-communities also showed different preferences in terms of bacterial community composition, as the former was enriched with Bacteroidetes while the latter had more Alphaproteobacteria and Betaproteobacteria. All applications of soil amendments significantly improved soil quality of newly created farmlands in whole maize cropping system. Rare sub-communitiy genera Niastella and Ohtaekwangia were enriched during the maize cropping process, and Nitrososphaera was enriched under the application of simple amendment group soil. Thus, Chinese medicine residue soil amendments with appropriate additives could affect soil rare and abundant sub-communities and enhance physicochemical properties. These findings suggest that applying soil composite amendments based on CHR in the field could improve soil microbial diversity, microbial redundancy, and soil fertility for sustainable agriculture on the Loess Plateau.

• Journal of Forest and Environmental Science
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• v.37 no.1
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• pp.25-34
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• 2021

This study was conducted at Sitakunda coastal afforestation range, comprised of four beats- Bansbaria, Bakkhali, Baterkhil and Bogachattar, in Chittagong. Afforestation effects on soil physicochemical properties in comparison to adjacent barren land were analysed. In the study area, an area of 3277.33 ha was planted with Sonneratia apetala, Avecinnia officinalis, Excoecaria agallocha, Bruguiera sexangula, Ceriops decandra from 1968 to 2011. We found positive soil physicochemical changes in plantations in comparison to adjacent barren land. Soil bulk density of plantation was lower than the adjacent barren land. Soil pH and soil salinity were significantly higher in barren land whereas soil organic matter, organic carbon, nitrogen, phosphorus, potassium of plantations were higher in afforested land. Soil texture ranged from clay loam to sandy loam in different depth of these two types of land. However, this study concludes that there is clear evidence that afforestation has positive impacts on all soil properties in different location and soil depths in the study area.

• Journal of Soil and Groundwater Environment
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• v.22 no.1
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• pp.27-32
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• 2017

Cesium (Cs) generated by nuclear accidents is one of the most hazardous radionuclides because of its gamma radiation and long half-life. Especially, when Cs is exposed on the soil environments, Cs is mainly adsorbed on the topsoil and is strongly combined with tiny soil particle including clay minerals. The adsorption of Cs onto soil can vary depending on various physicochemical properties of soil. In this study, the adsorption characteristics between soil and Cs were investigated according to various physicochemical properties of soil including organic matter contents, cation exchange capacity (CEC), soil particle size, and the types of clay minerals. Soil organic matter inhibited the adsorption of Cs onto the soil because organic matter was blocking the soil surface. In addition, it was estimated that the CEC of the soil influenced the adsorption of Cs onto the soil. Moreover, more Cs was adsorbed as the soil particles size decreased. It was estimated that Cs was mostly adsorbed onto the topsoil, this is related to the clay mineral. Therefore, soil organic matter, CEC, soil particle size, and clay minerals are considered the key factors that can influence the adsorption characteristics between soil and Cs.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.6
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• pp.85-94
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• 2004

This study was carried out to analyze physicochemical properties according to the soil height and to the six types of sites that were used as planting ground in the reclaimed land from the sea, Gwangyang Bay. The physicochemical properties of the soil types were tested by t-test(p<0.01, 0.05), at each of the 6 planting ground sites(p<0.01, 0.05), and at each height(p<0.01) of the planting grounds. These areas were tested by ANOVA and were significantly different. Improved soil was better than reclaimed soil from the sea for Zelkova growth because the improved soil contained lower amounts of pH, ECe, N $a^{+}$, $Ca^{++}$, $Mg^{++}$ SAR. Due to freedom from variables such as salt content in the underground as well as the physical and chemical disturbance of the soil, favorable planting ground for tree growth was recorded at the higher grounds than at the lower ones. Soil detriment to the tree growth in the studied sites included elements such as soil hardness, and the distribution of sodium in the tree root systems. The planting grounds for the favorable growth of landscape trees were determined in the following order: the grounds of mounding> the coved ground of improved soil, and the filled ground of improved soil.l.l.l.