• Korean Journal of Soil Science and Fertilizer
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• v.20 no.4
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• pp.321-326
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• 1987

This study was conducted to obtain the basic information on the application of S-fertilizer in the cultivating soil of Garlic. The distributions of cation and anion according to the soil depth in paddy field were examined. The average $SO_4{^{-2}}$ contents of surface and subsoil were 72.1 ppm and 45.1 ppm in paddy soils, and 53.1 ppm and 19.5 ppm in upland soils, respectively. In paddy soils, the contents of $SO_4{^{-2}}$ showed a positive correlation to the contents of organic matter, total nitrogen, exchangeable K, Ca, Mg and Fe. Whereas in upland soils, the contents of $SO_4{^{-2}}$ showed a positive correlation to the contents of organic matter and total nitrogen in surface soils. The exchangeable Ca and Mg contents were found to be higher with soil depth, however, the K contents was found to become very low. The $SO_4{^{-2}}$ contents was found to be higher with soil depth, indicating that $SO_4{^{-2}}$ should be leached from surface soils by percolated water.

• Journal of Soil and Groundwater Environment
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• v.7 no.1
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• pp.53-62
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• 2002

The physical and chemical properties of cover soils of 10 waste landfill sites in Kyonggi-Do area, where social circumstances at present forces to consider the reuse of landfill, were investigated to provide the informations of soil environment which are necessary to establish the appropriate ecological restoration plan of waste landfills. The pH and electrical conductivity of soils were higher in landfills sites than in reference sites (area around landfill sites), indicating the salt accumulation in surface soil. However, total-N and organic matter contents were lower in landfills sites than in reference sites. In landfill sites, the total-N and plant available-P contents were less than 0.15% and 20mg/kg, respectively. Exchangeable cations (K, Ca, Mg and Na) and heavy metal (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) contents varied between the landfill sites, but were higher in landfills sites than in reference sites. The major exchangeable cation of soil was Ca. Heavy metal contents were much lower than the critical concentration which phytotoxicity is considered to be possible and the standard for agricultural land of Korean Soil Environmental Preservation Act. Therefore, the proper soil management plan to increase the soil fertility is recommended for the ecological restoration of landfill using natural or artificial vegetation.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.519-524
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• 2013

pH buffer capacities (pHBC, $cmol_c\;kg^{-1}\;pH^{-1}$) of 6 residual Entisols derived from granite, granite-gneiss, limestone, sandstone, shale, and basalt in Korea were studied. Soil acidity may become a problem if the soil pH is reduced to critical levels when nutrient cycles are unbalanced (especially N, C and S). The relation between the pHBC and the physico-chemical properties of the 6 soils was also studied. In the A horizons of all the soils except Euiseong series developed from sandstone, the contents of clay, organic matter and cation exchange capacity (CEC) were higher than those of C horizon, but bulk density and pH were lower than C horizon. Clay content of Euiseong series decreased with soil depth, which might be caused by the elluviation. The soils developed from granite, granite-gneiss and sandstone have a higher $SiO_2$ content than those developed from basalt and limestone. The contents of $Fe_2O_3$ and MgO were high in the soils from developed from basalt, limestone and shale comparing with the soils from granite, granite-gneiss and sandstone. The soils from basalt and limestone showed higher values of ignition loss than those from the other parent rocks. The pHBC of the soils was ranged from 1.8 to 3.2 $cmol_c\;kg^{-1}\;pH^{-1}$ showing as follows : basalt, limestone > shale, granite-gneiss > granite sandstone.

• Journal of Ginseng Research
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• v.13 no.1
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• pp.84-91
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• 1989

This study was conducted to Investigate the effects of physico-chemical soil properties on the growth and yield of ginseng. 1 In the field survey, the yields of 6 year old ginseng were 2.46 Kg/3.3$m^2$, 2.13 Kg/3.3$m^2$, 1.44 Kg/3.3 $m^2$ in clay loam, loam and sandy loam soils, respectively 2. The missing plant rate for il year old ginseng were 33.6% and 51.6% in clay loam and sandy loam soils, respectively : the stem length and stem diameter of ginseng plants in sandy loam soil were smaller than those in clay loam soil. 3. Soil aggregation and porosity we're slightly higher in 6 year old ginseng fields than in 2 year ones. 4. Inorganic-N increased in 2 year and 3 year old ginseng fields reaching up to 100-120ppm, however it 1 decreased to 75 ppm, 34 ppm and 25 ppm in 4, 5 and 6 year old ginseng fields, respectively, It varied 1 more greatly in sandy loam soil than in clay loam. 5. The $P_2O_5$, K, Ca, and Mg contents differed little with plant age. Sandy loam had high N and $P_2O_5$ contents but low cation contents. 6. The yield of 6 year old ginseng fields were significantly correlated with clay contents and porosity. The missing Plant rate of 6 year old ginseng had a positive correlations with sand. and N contents.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.211-214
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• 1998

Changes in physico-chemical properties and major nutrient contents were investigated in the soil of paddy fields during fallow period. Weed vegetation change in the fallow paddy fields was also examined. As the fallow period became longer, organic matter content in the paddy soil has gradually increased. Soil pH of the paddy fields has not changed until three years of fallow period and thereafter slightly increased. Cation exchange capacity of the paddy soil, and exchangeable N, K, Ca and Mg contents in the soil tended to decrease until three years of fallow period and then increase with the prolonged fallow period. As the fallow period became longer, available $P_2O_5$ content in the paddy soil has continuously decreased. Available $SiO_2$ content in the paddy soil has not changed until three years of fallow period and thereafter increased. The vegetation in the fallow paddy fields have mostly been occupied by the weeds of the Gramineae, Cyperaceae, and Compositae. As the fallow period became longer, the weeds of the Polygonaceae and Juncaceae have increased, whereas the weeds of the Leguminosae, Commelinaceae, Pontederiaceae, and Onagraceae have gradually disappeared. However, the weeds of the Gramineae and Cyperaceae have always been dominant in the paddy fields during the fallow paddy period.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.2
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• pp.173-178
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• 1984

Correlation study was conducted to establish the optimum test level of soil improvement for good growth of corn from the relationships between the corn yield and soil chemical properties in 16 farmers' demonstration fields. Significant positive correlations between the corn yield and soil chemical properties ; pH, available phosphorus, exchangeable potassium, calcium, magnesium, cation exchange capacity. available silica, and base saturation percentage were showed but organic matter and nitrogen content were not. The proper nutrient contents in soil for expecting corn yield, 1.000kg/10a could be estimated as pH 5.6, available phosphorus 327ppm, exchangeable potassium 0.39me/100g, exchangeable calcium 5.5me/100g, exchangeable magnesium 1.3me/100g, cation exchange capacity 11.5me/100g, available silica 116ppm, base saturation percentage 58 from the relationships between the corn yield and soil chemical properties. Exchangeable aluminium were negatively correlated with not only corn yield but also pH, available phosphorus, exchangeable potassium and exchangeable calcium.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.215-220
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• 2011

In order to estimate the inorganic nutrient content in cucumber leaves at respective growth stages under greenhouse conditions, we investigated five cucumber farms practicing a forcing cultivation system with nine-month growth period and another five cucumber farms practicing a semiforcing cultivation system with six-month growth period. The cucumber yield in forcing and semiforcing cultivation systems amounted to 14.8 ton $10a^{-1}$ and 10.7 ton $10a^{-1}$, respectively. Soils between two different cultivation systems showed no significant differences in pH, organic matter contents and exchangeable cation contents during early growth stage, whereas EC, $NO_3$-N and available $P_2O_5$ contents were higher in soils of semiforcing cultivation systems. Suitable soil temperature was well provided by forcing cultivation. The highest NPK contents in leaves were observed in 60~80 days after planting for forcing systems and in 100 days after planting for semiforcing systems. Thereby forcing cultivation systems showed somewhat higher NPK contents. Ca and Mg contents in cucumber leaves did not significantly change during the growth period in forcing systems, while semiforcing systems showed the highest contents of Ca and Mg in 80~100 days after planting. Fe, Mn and Zn contents in leaves also did not significantly change during the growth period, whereas Mn contents were slightly higher in forcing systems due to lower soil pH. B contents in leaves were higher in semiforcing systems because of higher available B contents in soil.

• Economic and Environmental Geology
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• v.30 no.1
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• pp.51-60
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• 1997

The high radon (Rn222) potentials of soil, groundwater, hotspring and indoor environments in the Taejon city area were delineated by use of an EDA RDA-200 radon detector. The U and Th contents were also analysed using a Multi Channel Analyzer to illustrate the sources of the radon potentials. The average U concentrations in Taejon vary according to the type of granites such as $4.14{\pm}2.36ppm$ in schistose granite (SG), $3.13{\pm}1.70ppm$ in biotite granite (BG) and $3.01{\pm}1.95ppm$ in two mica granite (TG). The U contents in the granites are closely related with the amounts of uraniferous minerals. However, the U contents in the soil are found to be $5.05{\pm}4.75ppm$ in TG, $4.07{\pm}1.69ppm$ in BG and $3.87{\pm}1.91ppm$ in SG which are mainly explained by the different cation exchange capacities (CEC) of the soils from various granites. The levels of soil radon are $552{\pm}656pCi/l$ in SG, in which levels at two locations exceed the level of 1,350 pCi/l established as guideline for follow-up action by the U.S. Environmental Protection Agency (EPA), $443{\pm}284pCi/l$ in TG and $224{\pm}115pCi/l$ in the BG. The soil radon concentrations are found to be proportional to the U content and hardness of the soils. The groundwater radon concentrations in the domestic wells of - 30~-100 m depth show that $6,907{\pm}4,665pCi/l$ in TG, $5,503{\pm}6,551pCi/l$ in SG and $2,104{\pm}1,157pCi/l$ in BG which are positively related with U contents in soils. The radon levels of six groundwater wells in TG and two in SG are greater than guideline for drinking water level, 10,000 pCi/l by EPA (1986). Average radon contents of hotsprings and public bathes in the TG area are $7,071{\pm}1,942pCi/l$ and $1,638{\pm}709pCi/l$, respectively, which are below the EPA standard for remedial action value of the 10,000 pCi/l. The mean indoor radon concentrations of the TG and SG areas are $1.60{\pm}1.20pCi/l$ and $1.60{\pm}0.70pCi/l$, respectively. The elevated indoor radon levels of 5.6 pCi/l and 6.7 pCi/l are found to be particularly in TG area, which exceeds 4 pCi/i guideline, correlating positively with the U contents in the soil and radon concentration in the groundwater.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.2
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• pp.66-73
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• 2004

As one of the typical farming practices in the sloped upland in Pyeongchang and Hongcheon area, application of piling with coarse saprolite materials has been practiced by farmers for several reasons such as reduction of damage by monocropping, better development of plant roots, and better drainage. However, adverse effect on application of coarse saprolite soil materials to environmental aspects should not be ignored. Therefore, this research was conducted to evaluate the physicochemical properties of coarse saprolite materials in upland fields in Pyeongchang area. According to particle size distribution of coarse saprolite materials, averaged gravel contents for Pyeongchang and Hongcheon county were 16.7 and 25.3%, respectively. There was no significant difference in gravel contents by soil depth, and CV values for each particle size ranged from 20 to 40%, which implied that application of coarse material with similar properties. When we compared CEC values of dressed soil with or without considering gravel content, CEC values decreased as increasing gravel contents. The penetration resistances were 0.04-7.48 MPa at the 0 to 10 cm surface soil, and 0.10 to 8.80 MPa at the depth below 11 cm. The bulk density of the soil was $1.15g\;cm^{-3}$ at the surface soil and 1.29 to $1.35g\;cm^{-3}$ at the soil depth below 10 cm. The organic matter content, cation exchange capacity, and avaliable $P_2O_5$ concentrations of soil in upland where piling with saprolite materials of Pyeongchang area applied were $12.4g\;kg^{-1}$, $7.1cmol_c\;kg^{-1}$, and $526mg\;kg^{-1}$, respectively. Cation exchange capacity was lower than that of averaged Korean upland soil, while available $P_2O_5$ concentration was relatively higher than that of averaged Korean upland, which indicated high input of various fertilizers.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.5
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• pp.85-92
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• 2016

The eight mixes and artificial soil aggregates were prepared for evaluating the practical application of lightweight foamed concrete as soil aggregates. The main parameter was unit binder content ranged between from 100 to $800kg/m^3$. In lightweight foamed concrete, flow, slurry and dried density, and compressive strength at different ages were measured. In Artificial soil aggregates crushed from lightweight foamed concrete, particle size distribution, pH, coefficient of permeability, cation exchange capacity(CEC), and ratio of carbon to nitrogen(ratio of C/N), were measured. The test results showed that flow, slurry and dried density, and compressive strength at different ages of lightweight foamed concrete increased with the increasing of unit binder content. Compressive strength at age of 28, of lightweight foamed concrete with unit binder of more than $500kg/m^3$, was more than 4 MPa. The ammonium phosphate immersion time of more than age of 3, was effective to decrease pH of artificial soil aggregates. In addition, artificial soil aggregates was evaluated as high class in terms of cation exchange capacity(CEC), while satisfied with value of ratio of carbon to nitrogen(ratio of C/N) recommended by landscape specification.