• Asian Journal of Turfgrass Science
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• v.7 no.2_3
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• pp.129-135
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• 1993

Surface soils and aerial parts of Korean lawn(Zoysia koreana) at normal fair way of 4 golf courses and yellow discolored fairway of one golf course in Kyonggi province were taken at and analyzed for mineral contents in soil Mg and Ca were most deficient while EC was too high and phosphorus was exess. There were significant positive correlation between pH and Ca and between EC and total N. There was no consistent simple correlation between single component in soil and plant, indicating the involvement of multi-minerals in one mineral absorption. m mineral contents of aerial part Mg was severely low. potassium moderately but Ca was normal, Mg and Ca showed significant correlation in aerial part, yellow-discolored lawn showed the lowest content of Mg in aerial part and surface soil. Very high N and high phosphorus in aerial part inspite of low P in soil. The above facts indicates Mg deficiency in fair way soils in most golf courses resulting in yellow-discoloration in lawn.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.3
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• pp.170-179
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• 2015

This study was carried out to investigate the sustainable agriculture of no-tillage technique to minimize tillage problems under rain interception green house condition including recycling of the ridge and the furrow for following cultivation in Korea. Chemical properties in soils were investigated at 3-years after cultivation at conventional tillage [CT; 2-years no-tillage (2009-2010) and 1-year (2011) tillage] and no-tillage [NT; 2009-2011] field. Soil pH maintained between 5.8 and 6.0 irrespectively tillage and no-tillage. Salinity (EC), contents of total nitrogen (TN), cation exchange capacity (CEC), and exchangeable cations (K, Ca and Mg) in soil were remarkably higher in CT than in NT treatment. Salinity (EC), contents of OM, TN, CEC, and exchangeable cations in top soil and subsoil indicated higher deviation in CT than NT treatment. Organic matters and inorganic matters in soil were positive (+) correlation. Suppression of pepper growth and increase of yield were observed in no-tillage soil compared with tillage soil. These results indicated that no-tillage technique in crop culture could play an important role with respect to chemical properties in silt loam soil.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1114-1119
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• 2012

This study was conducted to assess the microbial toxicity of ionic silver solution ($Ag^+N$) and silver nanoparticle suspension ($Ag^0NP$) based on the Microtox bioassay. In this test, the light inhibition of luminescent bacteria was measured after 15 and 30 min exposure to aqueous solutions and soils spiked with a dilution series of $Ag^+N$ and $Ag^0NP$. The resulting dose-response curves were used to derive effective concentration (EC25, $EC_{50}$, EC75) and effective dose ($ED_{25}$, $ED_{50}$, $ED_{75}$) that caused a 25, 50 and 75% inhibition of luminescence. In aqueous solutions, $EC_{50}$ value of $Ag^+N$ after 15 min exposure was determined to be < $2mg\;L^{-1}$ and remarkably lower than $EC_{50}$ value of $Ag^0NP$ with $251mg\;L^{-1}$. This revealed that $Ag^+N$ was more toxic to luminescent bacteria than $Ag^0NP$. In soil extracts, however, $ED_{50}$ value of $Ag^+N$ with 196 mg kg-1 was higher than $ED_{50}$ value of $Ag^0NP$ with $104mg\;kg^{-1}$, indicating less toxicity of $Ag^+N$ in soils. The reduced toxicity of $Ag^+N$ in soils can be attributed to a partial adsorption of ionic $Ag^+$ on soil colloids and humic acid as well as a partial formation of insoluble AgCl with NaCl of Microtox diluent. This resulted in lower concentration of active Ag in soil extracts obtained after 1 hour shaking with $Ag^+N$ than that spiked with $Ag^0NP$. With longer exposure time, EC and ED values of both $Ag^+N$ and $Ag^0NP$ decreased, so their toxicity increased. The toxic characteristics of silver nanomaterials were different depending on existing form of Ag ($Ag^+$, $Ag^0$), reaction medium (aqueous solution, soil), and exposure time.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.2
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• pp.59-64
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• 2006

To analyze the changes of soil physico-chemical properties after reclamation, we carried out an experiment for 75 samples of representative saline soils in South Korea. The more the years after reclamation is proceeded, the blighter the soil color is, soil horizon differentiation and structure is developed, but electrical conductivity(EC) decreased. After the soil survey, coarse textured soils were more quickly de-salined than the fine textured soils. In case of fine loamy textured Poseung series, it could be estimated that the series had Salic horizons in sub-order level of taxonomical classification. In other case of coarse loamy textured soil series, it could be estimated that the series had Sodic properties in sub-group level. Sodium contents of fine loamy textured soils were not decreased after reclamation, but those of coarse loamy textured Gwanghwal series reclaimed about 76 years ago were reclassified because of desalinization. To be desalined low to 4 dSm-1 of EC, it presumably takes about 108, or 12 years for fine loamy and coarse loamy textured soils, respectively.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.271-278
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• 2009

This study was conducted to investigate the effect of the mixture ratio of the inorganic soil amendments on the soil physicochemical properties. In this experiment, three kinds of soil amendments which had similar pH, EC and particle size, the A, B and C, were tested. The mixture ratio of soil amendment were 0%, 3%, 5%, 7% and 10% (V/V) incorporated with sand which met to the USGA(United State of Golf Association) particle standard. To analyze the effects of amendment on chemical soil properties, pH, EC(electrical conductivity) and CEC(cation exchangeable capacity) were measured. The porosity, bulk density and hydraulic conductivity also measured to analyze the changes of physical properties. In the chemical properties, pH was significantly related to the mixture ratios of amendments, A and C(P<0.05), CEC and EC also related to the ratios of C(P<0.01). When the results were applied to the USGA standard of the soil physical properties, the optimum mixture ratios of each amendment were 3% in A and B, and 7~10% in C. To analyze the corelation of mixture ratio versus to physical character, volume of porosity was significantly related to the ratio of B (P<0.05), and showed similar corelation in porosity and hydraulic conductivity with ratio of C(P<0.05). These results indicate that types and mixture ratio of inorganic soil amendments should affect on soil physio-chemical properties of root zone on USGA sand green.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.6
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• pp.15-25
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• 2019

Contamination of soil by deicing salt is among the important environment problems due to their toxicity and negative impact to human health and the environment. One of the effective methods for cleaning the soil from deicing salts is desalination using soil amendment-phytoremediation continuum treatment. The purpose of this study was to determine how much of the pH, EC control and Ca²⁺, Na⁺, Mg²⁺, and K⁺ taken up soil amendments and Miscanthus sinensis, and to evaluate the effect of salt reduction and growth improvement as affected by soil amendment in high concentration of calcium chloride (CaCl₂) deicing salts. Results indicated that the addition of soil amendments was decrease the EC and pH, also significantly reduce the leaching of Ca²⁺, Na⁺, Mg²⁺, K⁺, a chloride ions related deicing salts, compared to the control for CaCl₂ 10 g/L treatment. It also resulted in an enhanced plant growth and higher plant height, leaf length, leaf width, number of leaves, fresh weight and dry weight in Hydroball treatment + Miscanthus sinensis planting continuum treatment compared to the treatment that planted Miscanthus sinensis only. Therefore, we concluded that soil amendments might be attributed to an accumulation of deicing slats in the roadside soil, resulting in the improvement of Miscanthus sinensis growth.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.4
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• pp.273-277
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• 2001

Traditional methods of chemical analysis for the soil properties take time and produce harmful waste. The purpose of this research was to evaluate an NIR technique for measuring some soil properties that are rapid and accurate in soil fertility assessments. The NIR instrument (InfraAlyzer 500, Bran & Luebbe Co.) was used for obtaining spectral data from 140 finely ground soil for calibrations and validation estimating pH, CEC, extractable Ca, Mg, K, $SiO_2$, humic acid and EC. Partial least square regression analysis was used to develop a calibration of NIR spectroscopy method. The results indicated that NIR spectroscopy could be used as a routine nondestructive method quantitatively determining soil chemical properties quickly. However the NIR technique may require sample preparation to obtain even diffuse reflection spectra from the soil and data manipulations to obtain optimal predictions.

• Journal of agriculture & life science
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• v.50 no.3
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• pp.69-80
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• 2016

The present study was to survey the site environment, vegetation structure and soil characteristics in the wild habitats of Acer tegmentosum Maxim. and offers basic information for habitats conservation and restoration. Most of the wild habitats were located at altitudes between 605~1,413m with inclinations ranged as 8~30°. The bare rock rate were 8~50%. The vegetation structure by the PC-ORD based on the Two Way Cluster Analysis were divided into three groups Community I(Acer tegmentosum - Quercus mongolica), Community II(Acer tegmentosum - Carpinus cordata), Community III(Quercus mongolica - Tilia amurensis). The species diversity(H') was highest in Community II as 1.474, Community I was 1.471, Community III was 1.219. The soil textures were Clay loam, The average soil pH was 4.8, Soil organic matter was 15.15% and available phosphorus was 2.33ppm. Ordination analysis result by soil characteristics, community, characteristic species showed that the greatest effect factors were slope, altitude, tree and shrub's cover rate, organic matter, total-nitrogen, calcium, magnesium. Correlation analysis between environment factor result showed that O.M. - (T.N., K+, Mg2+, CEC, EC), T.N. - (K+, Mg2+, CEC, EC) were positive correlations.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.334-339
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• 1985

A sweet corn hybrid, Honey Bantam, was planted on 24 May, 1984 in a silty clay loam soil to investigate the effects of polyethylene(P.E.) mulch and different levels and placements of Nitrogen(N) on soil properties and sweet corn growth. A split-split plot design with three replications was employed; P.E. mulch and bare soil were main plot, N levele of 8, 12, 16, and 20 kg/10a were subplot, and band and broadcast of fertilizers were sub-subplots. At early growth stage soil temperature under P.E. mulch was higher than that in bare soil by 5-10$^{\circ}C$, but the differences decreased as plant growth advanced. Soil hardness increased with soil depth while P.E. mulch reduced soil hardness probably by holding high soil moisture. Soil pH decreased up to the 6th week after planting and then increased in bare soil, but it contineously decreased up to the 8th weeks under P.E. mulch regardless N levels and placements. Electrical conductivity(EC) of soil increased up to the 6th weeks after planting and then decreased in all treatments except broadcast of fertilizers under P.E. mulch where EC increased contineously. Generally, soil EC under P.E. mulch was higher than that in broadcast. Broadcast of fertilizers did not affect emergence of seedlings in all N levels under P.E. mulch and bare soil, but band of fertilizers at all N levels under P.E. mulch and higher levels of N in bare soil reduced emergence rate significantly. Percent stand was possitively correlated with soil EC and it strongly influenced the number of marketable ears. Plant growth was enhanced and silking date was earlier by 14-19 days under P.E. mulch compared to bare soil probably due to increased soil moisture, reduced soil hardness and higher soil temperature.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.4
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• pp.411-418
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• 1996

This experiment was conducted to investigate the effect of electric conductivity (EC) and potassium (K) concentration level in the culture solution on the growth and the air pollution monitoring capability of Perilla frutescens Suwon 16 which was recognized as a possible bioindicator for air pollution. The plants were exposed to $NO_2$, $O_3$, $SO_2$ and $NO_2+SO_2$ within a phytotron at $25^{\circ}C$ (day) or at $20^{\circ}C$(night) with 70% of relative humidity and evaluated the effect of EC and K level on the injury of the plants, The highest dry weights were gained as 16.3 g/plant at 0.5 dS/m of EC and as 32.3 g/plant at 100 and 200mg/l of K concentration, respectively. The diffusive resistances appeared as low values at 0.5 dS/m of EC and at 50, 100mg/l of K concentration. The increasing of the visible injury with increasing the dose of air pollutants could be taken at 0.5. 1.0 ds/m of EC and at 50, 100mg/l of K. The recommendable level of EC and K of the culture solution were 0.5-1.0 dS/m of electric conductivity. 50-100mg/l of K for the plant as an air pollutant biomonitor, when the 7th or 8th leaf was developed.