• Korean Journal of Environmental Agriculture
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• v.41 no.2
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• pp.101-107
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• 2022

BACKGROUND: Soil amendment was necessary applied for the sand that had been used to root zone of green ground in golf course because of its low water retention power and cation exchangeable capacity. This study was conducted to evaluate the effect of the mixed ratio of peat moss and coconut coir as soil amendment materials on the soil physicochemical properties applied to rootzone based on sand. METHODS AND RESULTS: The soil amendments were blended at 0, 3, 5, 7 and 10% by soil volume. The pH in the peat moss treatment was lower than that of control (0% soil amendment), and pH and electrical conductivity (EC) in the coconut coir were higher. The blending ratio of peat moss was negatively correlated with pH of rootzone soil (p<0.01), and that of coconut coir positively with EC (p<0.01). As compared with control, capillary porosity, the physical factors such as air-filled porosity, total porosity, and hydraulic conductivity of rootzone soil were increased by applying peat moss and coconut coir. For correlation coefficients between percentage of soil amendments and soil physical factors, peat moss and coconut coir were positively correlated with porosity and hydraulic conductivity (p<0.01). CONCLUSION(S): These results indicated that the application of peat moss and coconut coir affected on the change of physicochemical properties of rootzone soil, and improved soil porosity and hydraulic conductivity.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.411-414
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• 2006

This study was examined to determine hydraulic conductivity of vadose zone($K_s$) and effective porosity(${\phi}_e$) of undisturbed soil profiles collected at each vadose zone of 6 study areas in South Korea. Effective porosity was approximately 19% of total porosity for each soil profile. Applied to Ahuja's equation, the correlation between $K_s$ and ${\phi}_e$ showed $y=1.3{\times}10^{-7}x^{2.15}(r^2=0.37)$ for total soil profiles. Although the small numbers of soil profile were used for this study, the result of this study might be used for other soil hydraulic studies as reasonable data.

• Geomechanics and Engineering
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• v.28 no.1
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• pp.77-87
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• 2022

Many geotechnical analyses require the investigation of water flow within partially saturated soil zone to incorporate the effect of climatic conditions. It is widely understood that the hydraulic properties of the partially saturated soil should be included in the transient seepage analyses. However, the characteristics of dual porosity soils with dual-mode water retention curve are normally modelled using single-mode mathematical equation for simplification of the analysis. In reality, the rainwater flow can be affected significantly by the dual-mode hydraulic properties of the soil. This paper presents the variations of safety factor for dual porosity soil slope with dual-mode water retention curve and dual-mode unsaturated permeability. This paper includes the development of the new dual-mode unsaturated permeability to represent the characteristics of soil with the dual-mode water retention curve. The finite element analyses were conducted to examine the role of dual-mode water retention curve and dual-mode unsaturated permeability on the variations of safety factor under rainfall loading. The results indicate that the safety factor variations of dual porosity soil slope modelled using the dual-mode water retention curve and the unsaturated permeability equation are lower than those of dual porosity slope modelled using single-mode water retention curve and unsaturated permeability equations.

• Journal of Ginseng Research
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• v.9 no.1
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• pp.36-41
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• 1985

The study was conducted to investigate the changes of soil physico-chemical properties between soils of preplanting fields and 2 years old ginseng fields, and compare the missing plant rate among the 2 years 016 ginseng fields. 1, The missing plant rate of 2 years old ginseng was high in sand loam while low in clay loam soil texture, soil porosity and NO3-N were remarkably increased in 2 years old ginseng field than preplanting soil, as the clay content was increased, soil porosity seemed to be increased but exchangeable nitrogen decreased. 2. The preplanting soil management methods did not significantly influenced on the missing plant rate and soil porosity in 2 years old ginseng fields, However NO3-N content and Fusarium density seemed to be decreased as the plow frequency was increased, exchangeable nitrogen content, whereas, seemed to be increased with more organic matter. 3. Differences of clay content (below 15% and above 20% of clay content) was significantly influenced on soil porosity, bulk density, total nitrogen, organic matter and P2O5 content. 4, Missing rate showed negative correlation with clay, soil moisture, and organic matter content but positive corelation with NO3-N in 2 years old ginseng fields.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.4
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• pp.225-234
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• 2014

This study was carried out to investigate the sustainable agriculture of no-tillage technique including recycling of the ridge and the furrow of a field for following crops in Korea. No-tillage systems affect soil physical properties such as three phase (solid, liquid, and air phase) and distribution of soil granular. Solid ratio of subsoil in 3-year of no-tillage (NT) treatment was remarkably lower than that in conventional (CT, 2-year of no-tillage + 1-year of tillage) treatment, while air ratio of subsoil in NT remarkably increased. Bulk density of subsoil in NT remarkably decreased. Porosity of subsoil in NT remarkably increased. Deviation of air phase, bulk density, and porosity of top soil and subsoil in NT remarkably decreased in NT compared with CT. Solid phase ratio and liquid phase ratio in NT and CT had positive (+) correlation. Solid phase ratio and air phase ratio in NT and CT had negative (-) correlation, also liquid phase ratio and air ratio had negative (-) correlation. Bulk density and liquid ratio in soil had positive (+) correlation at top soil and subsoil in NT. Bulk density and air ratio in soil had negative (-) correlation in NT and CT. Porosity and liquid phase ratio had negative (-) correlation, r =1), the significant value was lower in NT than in CT. Porosity and air phase ratio had positive (+) correlation (r =1).

• Journal of the Korean GEO-environmental Society
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• v.14 no.5
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• pp.41-47
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• 2013

Well-graded and dense soils have good engineering properties. Unsaturated soil properties such as shear strength, compressibility and permeability are closely related to the soil-water characteristic curve of the soil. Therefore it is important to study the effects of the coefficient of uniformity and the porosity on the soil-water characteristic curve of the sandy soils, which are also related to the grain size distribution and the density of the soil, respectively. In this study soil-water characteristic curves (SWCCs) for six sandy soil specimens were investigated using Tempe pressure cells. The test data were best-fitted to Fredlund and Xing equation. The obtained fitting parameters and the characteristic points of SWCCs were discussed and correlated with the porosity and the coefficient of uniformity of the specimens. The results show that the smaller the porosity of the specimen becomes, the larger the value of the residual matric suction becomes, whereas the larger the coefficient of uniformity of the specimen becomes, the larger the value of the residual matric suction becomes. Regardless of the coefficient of uniformity, the smaller the porosity of the specimen, the flatter the max. slope of SWCC.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.215-221
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• 2006

This study focuses on investigating the effect of porosity-controlled earthenware on fermentation of kanjang, Korean soy sauce. Porosity of fermentation vessel was controlled by changing the mixing ratio of raw soils at manufacturing earthenware. Earthenwares contented 0%, 40% and 60% of the mixture of red brown soil and powdered soil (1 : 1), respectively. The more contents of the mixed soil, the more porosity in earthenware. During fermentation of kanjang in porosity-controlled earthenwares at $30^{\circ}C$ for 4 months, physical, chemical, microbiological and sensory quality attributes were monitored. Compared to other containers, kanjang in the earthenware that had 0% mixed soil showed less water loss, salt content and pH. It also produced higher total acidity, protease activity, total nucleotide, and microbiological changes which included total aerobic bacteria, lactic acid bacteria and yeast. Total nitrogen and free amino acids in kanjang did not show the consistency with the mixed soil contents of fermentation containers, which may take more effect of other factors as water loss than the porosity of vessels. However, the percentage of glutamic acid in total free amino acids was a little higher in the earthenware that had 0% of mixed soil than other containers. These positive physicochemical, microbiological changes also resulted in higher sensory quality.

• Magazine of the Korean Society of Agricultural Engineers
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• v.33 no.2
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• pp.120-129
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• 1991

This study refers to temporal variation of physical properties of tilled soil under natural rainfalls. Field measurements of porosity, average hydraulic conductivity and average capillary pressure head on a tilled soil were conducted by soil sampler and air-entry permeameter respectively at regular intervals after tillage. Temporal variation of these physical properties were analysed by cumulative rainfall energy since tillage. Field experiment was conducted on a sandy loam soil at Suwon durging April~July in 1989. The followings are a summary of this study results ; 1. Average porosity just after tillage was 0.548cm$^3$/cm$^3$. As cumulative rainfall energy were increased in 0.1070, 0.1755, 0.3849 J/cm$^2$, average porosity were decreased in 0.506, 0.4]95, 0.468m$^3$/cm$^3$ respectively. 2. Average hydraulic conductivity just after tillage was 45.42cm/hr. As cumulative rainfall energy were increased in 0.1755, 0.2466, 0.2978, 0.3849J/cm$^2$ average hydraulic conductivity were decreased in 15.34, 13.47, 9.58, 8.65cm/hr respectively. 3. As average porosity were decreased in 0.548, 0.506, 0.495, 0.468cm$^3$/cm$^3$ average capillary pressure head were increased in 6.1, 6.7, 6.9, 7.4cm respectively. 4. It was found that temporal variation of porosity, average hydraulic conductivity on a tilled soil might be expressed as a function of cumulative rainfall energy and average capillary pressure head might be expressed as a function of porosity. 5. The results of this study may be helpful to predict infiltration into a tilled soil more accurately by considering Temporal variation of physical properties of soil.

• Asian Journal of Turfgrass Science
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• v.24 no.2
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• pp.205-210
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• 2010

This study was conducted to investigate the effect of the mixed ratio of the soil amendments, peat, humate, peatmoss and zeolite, on the soil physicochemical properties. The mixed ratios of soil amendments were 0%, 3%, 5%, 7% and 10% (v/v) incorporated with sand which met to the USGA (United State of Golf Association) recommendation. It was measured pH, EC and CEC as a chemical properties. Porosity, capillary porosity, air-filled porosity, bulk density and hydraulic conductivity were also measured to analyze the changes of physical properties. Chemical properties were significantly different by mixture ratios of peat, humate, peatmoss and zeolite. When the results were applied to the USGA standard of the soil physical properties, the optimum mixture ratios of peat, humate and peatmoss were 5%, 3% and 7%, respectively. Air-filled porosity was factor involved in soil physical properties by blending with soil amendments and it was affected on volume of porosity and hydraulic conductivity. To analyze the corelation of mixture ratio versus to physical characters, the ratio of peat and peatmoss was significantly related to capillary porosity and hydraulic conductivity (P<0.05), that of humate hydraulic conductivity (P<0.01), and that of zeolite air-filled porosity and volume of porosity (P<0.05). These results could be used as a basic data for construction USGA sand green.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.127-133
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• 2008

The electrical resistivity methods have been commonly used for figuring out the ground layers. The purpose of this paper, differently from previous methods, is not only to figure out the layers but also to develope a equipment and a method to analyze ground porosity. Equipment has a shape of cone, which can be coupled with drilling rods. A field penetration test was performed to test application in Incheon Chungla area. Through the field test soil resistances were measured. To calculate soil porosity along the depth, Archie's law is applied. The results show that a new equipment and porosity analysis method using Archie's law can distinguish soil layers and precisely measure soil porosity.