• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.4
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• pp.253-258
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• 2001

This pot experiment was conducted to find out the forage productivity and quality in a grasslclover sward as affected by the application of three different fertilizers; double superphosphate(DS), fused Mg-phosphate (FP), and complex fertilizer(CF) on newly reclaimed hilly soil. This part was concerned with the mutual balances of mineral nutrients in the soils and mixed grass/clover sward in relation to grass tetany hazard. The results obtained are summarized as follows : 1. Concentration of exchangeable Mg and relative proportion of Mg to CEC in the soils before experiment were considerably below the critical level for good forage growth and prevention of grass tetany. It seems that these properties would be able to handicap by liming and NPK applications. 2. Comparing with the critical level for likelihood of tetany(Mg <0.2%, K >2.5%, and W(Ca+Mg) >2.2 in forages), mean concentration of Mg ranged from 0.14 in DS plot and 0.18 in FP plot to 0.24% in CF plot. Meanwhile, hazards of grass tetany in relation to the %K and ratio of K/(Ca+Mg) were not recognized. 3. Comparing with the optimum level of Carp(% ratio)=2.0 in forages for animal health, these ranged from 6.1 to 7.1. (Key words : Grass tetany, Fertilizer. Soil. Mineral nutrients)

• Korean Journal of Soil Science and Fertilizer
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• v.5 no.1
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• pp.17-23
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• 1972

The effect of completed mineral fertilizer on barley was investigated on ordinary upland and newly recrimed soil derived from granite, basalt and shale. 1. Yield of barley grains with application of completed meneral fertilizer 1 level varied from 100.8% to 233.1% on various soils in different parents rock, and 2 levels of the fertilizer varied from 250.1% to 309.5% on ordinary upland and newly recrimed soil derived from granite compared with control plot. But no effect on newly recrimed soil derived from basalt and shale. 2. $P_2O_5$, MgO and B contents in straw were increased, but Mn contents was decreased on all of soil. N contents in straw was decreased on the soil derived from granite, but $K_2O$ contents was increased on the soil derived from basalt and shale. 3. Relation between the yield and absorbed nutrient had related with positive correlection of 1-5%. 4. N and Mn contents in soil were decreased by application of completed mineral fertilizer, but soil pH, C.E.C. $Av-P_2O_5$, Ex-CaO, Ex-MgO and B contents were increased. Especially soil pH and C.E.C. were increased remarkably. 5. Relation between the yield and Ex-CaO and Ex-MgO contents in soil had related with positive correlation, but Mn contents had related with negative correlation.

• Korean Journal of Organic Agriculture
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• v.21 no.1
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• pp.69-78
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• 2013

This study was carried out to evaluate nitrogen availability of applied fertilizer and to investigate yield and growth of Korean kimchi cabbage as affected by amount of fertilizer and soil fertility in organic farming applied various fertilizers in rainshelter. The head weight of Korean kimchi cabbage cultured in infertile soil (sand loam) with no amendments was very low. and that in fertile soil (clay loam) was higher than in infertile soil (sand loam). The head weight of Korean kimchi cabbage as affected by amount of fertilizer was more variable in infertile soil (sand loam) than in fertile soil (clay loam). Nitrogen availability of applied fertilizer by Korean kimchi cabbage was lower in fertile soil (clay loam) than in infertile soil (sand loam) and the lower that was, the more fertilizer applied. By application of poultry manure compost 20Mg ha-1 and natural mineral materials such as guano, phosphate rock, and potassium magnesium rock equal to amount of fertilizer recommended in conventional farming, the yield of Korean kimchi cabbage in infertile soil (sand loam) with 1% organic matter came up to 90% of the yield in fertile soil (clay loam) with 6% organic matter. Therefore natural mineral materials such as guano for N source, phosphate rock for P source, and potassium magnesium rock for K source may be able to use as environmental-friendly fertilizers in organic Korean kimchi cabbage production in highland.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.3
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• pp.205-212
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• 2014

Chronological changes of soil organic carbon (SOC) must be prepared by IPCC guidelines for national greenhouse gas inventories. IPCC suggested default reference SOC stocks for mineral soils and relative stock factors for different management activities where country own factors were not prepared. 3.4 million data were downloaded from agricultural soil information system and analyzed to get chronological changes of SOC for some counties and for land use in Korea. SOC content of orchard soil was higher than the other soils but chronological SOC changes of all land use had no tendency in differences with high standard deviation. SOC contents of counties depended on their own management activities and chronological SOC changes of districts also had no tendency in differences. Thus, Korea should survey the official records and relative stock factors on management activities such as land use, tillage and input of organic matter to calculate SOC stocks correctly. Otherwise, Korea should establish a model for predicting SOC by analyzing selected representative fields and by calculating SOC differences from comparing management activities of lands with those of representative fields.

• Korean Journal of Soil Science and Fertilizer
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• v.7 no.4
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• pp.197-200
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• 1974

PCP adsorption experiment was carried out with six soils various in clay mineral and organic matter content and soil pH. The results were as follows; 1. The major factor governing the PCP adsorption is pH 2. The adsorption was increased with organic matter content at a certain pH 3. The adsorption was less related to crystalline clay mineral species.

• Journal of the Korean Professional Engineers Association
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• v.45 no.6
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• pp.28-32
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• 2012

Namhae chemical is one of the largest fertilizer manufacturing company in Korea which company has operating 4 unit agitator gear boxes and producing variety kinds of fertilizer production. The gearbox operating temperature of agitator is approximated in $55^{\circ}C{\sim}90^{\circ}C$ and required to keep operating continuous without stopping. The system required high performance oil and longer oil drain interval as limited workforce in maintenance team. It was lubricated by mineral gear oil of ISO VG 320 and also need to change to new oil frequently. Namhae Chemical would expect to keep stable operating condition without shut down and consider, lower cost of operation and equipment protection.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.1
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• pp.1-7
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• 2015

Global population is expected to reach nine billion in 2050 and the total demand for food is expected to increase approximately by 60 percent by 2050 as compared to 2005. Therefore, it is important to increase crop production in order to meet the global demand for food. Slow release fertilizers have been developed and designed in order to improve the efficiency of fertilizers. Mineral-based slow release fertilizers are useful because the minerals have a crystalline structure and are environmentally friendly in a soil. This review focuses on slow release fertilizers based on montmorillonite, zeolite, and layered double hydroxide phases as a host for nutrients, especially N. Urea was successfully stabilized in the interlayer space of montmorillonite by the formation of urea-Mg or Ca complex, $[(Urea)_6Mg\;or\;Ca]^{2+}$ protecting its rapid degradation in soils. Naturally occurring zeolites occluded with ammonium nitrate and potassium nitrate by molten salt treatment could be used as slow release fertilizer because the occlusion process increased the capacity of zeolites to store nutrients in addition to exchangeable cations. Additionally, surface-modified zeolites could also be used as slow release fertilizer because the modified surface showed high affinity for anionic nutrients such as nitrate and phosphate. Moreover, there were attempts to develop and use synthetic layered double hydroxide as a carrier of nitrate because it has positively charged layers which electrostatically bond nitrate anions. Kaolin was also tested by combining with a polymer or through the mechanical-chemical process for slow release of nutrients.

• Korean Journal of Soil Science and Fertilizer
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• v.26 no.4
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• pp.278-283
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• 1993

Gimhae series has a high content of jarosite mineral which is evoluted in soils from sediments rich in sulfur. Chemical compositions of jarosite mineral and soil samples were analyzed with water and various extraction solutions to evaluate the pedogenetic processes of the soil. The pH of jarosite mineral and $Bg_3$ horizon are below 4.0 and not much changed after incubation of dry samples rich in jarosite. The pedogentic formation of jarosite was identified through the chemical analysis indicating that cations and anion of K, Na, Al and S are present in abandance in $Bg_2$ and $Bg_3$ horizons.

• Economic and Environmental Geology
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• v.28 no.2
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• pp.147-154
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• 1995

Coal fly ashes collected from the Samcheonpo and the Seocheon Power Plants were analyzed for major and minor components and heavy metals such as As, Cd, Co, Cr, Cu, Ga, Hg, Mo, Ni, Pb, Sb, V and Zn in order to suggest basic data to apply coal fly ash as fertilizer or soil ameliorator. The specific gravity of the samples was less than 2.0, and amounts of organic matter range from 5.0% to 12.3%. The identified minerals by XRD were mainly quartz, mullite and pyrite in anthracite coal, and mainly quartz and mullite in bituminous coal. Generally, the contents of heavy metal elements analyzed were lower less than those of soil, though higher in some samples. Element couples of some elements( e.g., As-Mo, Zn ; Mo-As, Sb, V, Zn ; Sb-Zn ) show positive correlations with each other, but the high correlations of toxic elements such as As, Pb, Cd and Hg indicate to give attention to apply coal fly ash as fertilizer or soil ameliorator.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.3
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• pp.228-233
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• 1993

Method for the sun curing dehydration of pig excreta by using vinyl house was described. We determined effects of the dehydrated pig excreta on the yields of whole crop corn and proximate chemical composition of whole crop corn. Pig excreta were dehydrated upto 15% of moisture content by the 3-4 days of sun curing dehydration in vinyl house in the summer period. There was no significant difference between the dehydrated pig excreta treatment and the chemical fertilizer treatment on dry matter(DM) content, DM yield and crude protein contents of whole crop corn. Ca and Mg contents by the dehydrated pig excreta treatment were lower than those by thechemical fertilizer treatment. In the contrast, K content by the dehydrated pig excreta treatment was higher than those by the chemical fertilizer treatment. and dehydrated pig excreta treatments were higher in K/Ca+Mg ratio than chemical fertilizer treatment. These results suggested the availability of the sun curing dehydration of pig excreta in vinyl house in small-scale animal industry. In addition, the dehydrated pig excreta treatment showen similar effects to the chemical fertilizer treatment on dry matter yields and contents of chemical composition of whole crop corn. These results suggest that using the sun curing dehydration of pig excreta could reduce the chemical fertilizer cost. However, we need more study to the relationship between the unbalanced mineral contents and animal health.