• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.772-778
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• 2012

In order to develop the application method of compost manure (CM) and liquid manure (LM) for rice cultivation, experiments were conducted at silty loam paddy field in Gochang, Jeonbuk, a LM applied rate as N%; non-application, chemical fertilizer (CF) 100%, CM 50%+LM 50%, CM 30%+CF 70% and CM 30%+LM 70% as basal and additional fertilizer. $NH_4^+$-N content in paddy soil was higher with CF 100% application than the split application of compost and liquid pig manure fertilizer during the early stage of rice growth. However, there was no significant difference in the later part of rice growth. Amount of $NO_3^-$-N in leachate was decreased in CM 30%+LM 70% and CM 30%+CF 70% split applications compared to CF 100%. Amounts of OM and Avail $P_2O_5$, Exch. cations in soil of experiment after were highest with the split application of CM 50%+LM 50% and CM 30%+LM 70%. Amount of nutrient uptake of plants were no significant difference between the split application plots of CM and LM, but nitrogen utilization rate was 66% in average CM 50%+LM 50% and CM 30%+LM 70% to compared CF 100%. The rice yield of CM 50%+LM 50% was lower (90%) comparing that of CF 100% ($557kg\;10a^{-1}$). But the yield in CM 30%+CF 70% and CM 30%+LM 70% reached 96% in average, which did not show significant difference with that of CF 100%. Accordingly, LM 70% or CF 70% split application after CM 30% application was helpful in enhancing the physicochemical property of soil as well as reducing CF. It could be evaluated that this application in segmentation was better in productivity improvement and soil pollution reduction than the esinultaneous application of LM 100% in terms of split application in times of requirement for plants.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.463-468
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• 2013

The level of nitrous oxide ($N_2O$), a long-lived greenhouse gas, in atmosphere has increased mainly due to anthropogenic source, especially application of nitrogen fertilizers. Quantifying $N_2O$ emission from agricultural field is essential to develop national inventories of greenhouse gases (GHGs) emission. The objective of the study was to develop emission factor to estimate direct $N_2O$ emission from agricultural field in Gangwon-do, Korea by measuring $N_2O$ emissions from potato (Solanum tuberosum), red pepper (Capsicum annum L.), and Chinese cabbage (Brassica campestris L.) cultivation lands from 2009 to 2012. Accumulated $N_2O$ emission was $1.48{\pm}0.25kg$ $N_2O-N\;ha^{-1}$ for red pepper, $1.27{\pm}0.27kg$ $N_2O-N\;ha^{-1}$ for potato, $1.49{\pm}0.06kg$ $N_2O-N\;ha^{-1}$ for Chinese cabbage cultivated in spring, and $1.14{\pm}0.22kg$ $N_2O-N\;ha^{-1}$ for fall Chinese cabbage. Emission factor of $N_2O$ calculated from accumulated $N_2O$ emission, nitrogen fertilization rate, and background $N_2O$ emission was $0.0051{\pm}0.0016kg$ $N_2O-N\;ha^{-1}$ N for cropland in Gangwon province. More extensive study is deserved to be conducted to develop $N_2O$ emission factor for upland crops in Korea through examining the emission factors from various regions and crops because $N_2O$ emission is influenced by many factors including climate characteristics, soil properties, and agricultural practices.

• Horticultural Science & Technology
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• v.33 no.6
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• pp.845-853
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• 2015

The objective of this study was to predict the timing of nitrogen (N) demand through analyzing chlorophyll fluorescence (ChlF), soil-plant analysis development (SPAD), and normalized difference vegetation index (NDVI), which are positively correlated with foliar N concentration in star cluster (Pentas lanceolata). The plants were grown in potting soil under optimal conditions for 30 d, followed by weekly irrigation with five concentrations (0, 4, 8, 16, and 24 mM) of N for an additional 30 d. These five N application levels corresponded to leaf N concentrations of 2.62, 3.48, 4.00, 4.23, and 4.69%, respectively. We measured 13 morphological and physiological parameters, as well as the responses of these parameters to various N-fertilizer treatments. The general increases in Dickson's quality index (DQI), above-ground dry weight (DW), total DW, flowering rate, ${\Delta}F/Fm$', and qP in response to treatment with 0 to 8 mM N were similar to those of SPAD, NDVI, and Fv/Fm. Consistent and strong correlations ($R^2$= 0.60 to 0.85) were observed between leaf N concentration (%) and SPAD, NDVI, ${\Delta}F/Fm$', and above-ground DW. Validation of leaf S PAD, NDVI, and ${\Delta}F/Fm$' revealed that these vegetation indices are accurate predictors of leaf N concentration that can be used for non-destructive estimation of the proper timing for N-solution irrigation of P. lanceolata. Moreover, irrigation with 8 mM N-fertilizer i s recommended w hen leaf N concentration, SPAD, NVDI, and ${\Delta}F/Fm$' ratios are reduced from their saturation values of 4.00, 50.68, 0.64, and 0.137%, respectively.

• Microbiology and Biotechnology Letters
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• v.18 no.5
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• pp.530-534
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• 1990

A strain of actinomycetes, Thermoactinomyces sp. CH-53, was isolated from manure and composted livestock feces. Actinornycetes-feed additive was prepared with the solid wheat bran medium of Thermoactinomyces sp. CH-53 that grew vigorously on unsterilized poultry feces at $50^{\circ}C$. pH 6.5- 9.5 and moisture content of 55-65% and added at a rate of 1% (wtlwt) to the commercially assorted feed to be fed poultry. The excreted feces contained $10^7-10^8$. Thermoactinomyces sp. CH-53 cells per gram. Poultry feces malodour was got rid of during treatment. The effect on plant growth was evaluated on the basis of the amount of nitrogen as fertilizer under a loading of 0.2g N1600g soillpot. A11 samples were showed a promotion effect for plant growth. The treated poultry feces added from O.lg to 0.4g total nitrogen per 600g soil in a pat increased the growth of Brassica rapa var. perui-ridis.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.598-603
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• 2014

The level of nitrous oxide ($N_2O$), a long-lived greenhouse gas, in atmosphere has increased mainly due to anthropogenic sources, especially application of nitrogen fertilizers. Quantifying $N_2O$ emission in the agricultural field is essential to develop National inventories of greenhouse gases (GHGs) emission. The objective of this study was to develop emission factor to estimate direct $N_2O$ emission from agricultural field by measuring $N_2O$ emissions in the red pepper cultivating field from 2010 to 2012. Emission factor of $N_2O$ calculated from accumulated $N_2O$ emission, nitrogen fertilization rate, and background $N_2O$ emission was $0.0086{\pm}0.00043kg$ $N_2O-N\;kg^{-1}$ N resulted from three year experiment of the research sites. More extensive studies need to be conducted to develop $N_2O$ emission factors for other upland crops in the various regions of Korea because $N_2O$ emission is influenced by many factors including climate characteristics, soil properties, and agricultural practices.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.3
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• pp.163-169
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• 2015

The level of nitrous oxide ($N_2O$), a long-lived greenhouse gas, in atmosphere has increased mainly due to anthropogenic sources, especially application of nitrogen fertilizers. Quantifying $N_2O$ emission in the agricultural field is essential to develop national inventories of greenhouse gases (GHGs) emission. The objective of this study was to develop an emission factor to estimate the direct $N_2O$ emission from an agricultural field cultivated with the Chinese cabbage during autumn season in 2010-2012. Emission factor of $N_2O$ calculated over three years experiment using accumulated $N_2O$ emission, nitrogen fertilization rate, and background $N_2O$ emission was $0.0058{\pm}0.00254kg\;N_2O-N\;kg^{-1}\;N$. More extensive studies need to be conducted to develop $N_2O$ emission factors for other upland crops in the various regions of Korea because $N_2O$ emission is influenced by many factors including climate characteristics, soil properties, and agricultural practices as well as crop species.

• Journal of The Korean Society of Grassland and Forage Science
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• v.9 no.2
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• pp.82-87
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• 1989

A field experiment was carried out to determine the effects of 11 different application levels of nitrogen (N), phosphorous ($P_2O_5$) and potassium($K_2O$) fertilizer in late-autumn on the winter survival, early spring growth and dry matter(DM) yield, carbohydrate reserves (CHO-R) in stubble of grasses, and botanical composition in orchardgrass dominated existing pasture in Suwon from October, 1987 to May, 1988. Winter survival of grasses was high (ca. 90%) in all N-fertilized plots, regardless of $P_2O_5$ and $K_2O$ application, and those in zero-N and zero-NPK plots were low as 86.5% and 81.4%, respectively. Early spring growth was vigorous in N-fertilized plots. Heading rate at the fist harvest was 80-86% in all N plots, regardless of $P_2O_5$ and $K_2O$, while those in zero-N and zero-NPK plots were very low as 61% and 56%, respectively. The DM yield of first harvest was higher in the plots of N 35 kg(Site B) and N 70kg $ha^{-1}$ (Site A), regardless of $P_2O_5$ and $K_2O$ level, and those in zero-N and zero-NPK plots were very low (p < 0.05). But no significant difference of yield was observed between N 75 kg and N 105 kg. CHO-R in stubble and legumes were high in zero-N and zero-NPK plots, and low relationship was found between winter survival and CHO-R of grasses. Winter survival, early spring growth and DM yield were significantly influenced by N fertilizer. In this experiment, the optimum application level of N in late-autumn could be recommended in 35-70 kg $ha^{-1}$, and no beneficial effects were observed by $P_2O_5$ and $K_2O$ fertilizer.

• Korean Journal of Environmental Agriculture
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• v.31 no.1
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• pp.1-8
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• 2012

BACKGROUND: Organic fertilizers in watermelon cultivation are widely used to supply nutrient and organic matter. This study was conducted to investigate the effects of application rate of organic fertilizer on the watermelon growth and soil chemical properties in greenhouse METHODS AND RESULTS: The organic fertilizers used in this experiment were mixed expeller cake (MEC) and mixed organic fertilizer (MOF). The treatments were conducted with 4 levels (1.0 N, 0.7 N, 0.5 N and 0.3 N) on the basis of soil testing nitrogen fertilization (STNF) using MEC or MOF as the basal dressing, and using chemical fertilizers (CF) as the additional dressing on the rest of STNF. These fertilizations were compared to CF 1.0 N (0.3 N as the basal and 0.7 N as the additional dressing) and non fertilization (NF). The leaf area of watermelon in treatment 0.5 N and 0.3 N using MEC or MOF was similar to CF treatment. The absorbed nutrient amounts by leaf, weight and sugar contents of fruit in the 0.5 N and 0.3 N treatments were higher than other treatments. In 0.5 N and 0.3 N treatments using MEC or MOF on the basis of STNF, soil chemical properties such as electrical conductivity (EC), available $P_2O_5$ and exchangeable K concentrations after experiment showed tendency to decreasing or similar level before experiment. CONCLUSION(s): These results suggest that the MEC or MOF application as the basal dressing at the 30~50% level of STNF and CF application as the additional dressing on the rest of STNF be best to maintain adequate nutrient of soil and to increase marketable yield for watermelon.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.6
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• pp.493-497
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• 2000

An experiment was conducted to evaluate the possibility of using basic oxygen furnace (BOF) slag as soil conditioner in soybean upland field. In 1997, soybean (Glycine max L. cv. Eunha) crop was cultivated under different application rates of BOF slag at an experimental field of Chonnam Rural Development Administration in Nampyung, Najoo city. Five treatments, four application rates of BOF slag (0, 4, 8, $12Mg\;ha^{-1}$) and one application rate of lime ($2Mg\;ha^{-1}$) were tried with three replications. Plant height and shoot dry weight per plant were measured five times during the growth period. Chemical contents of soybean plant tissues and soil were also measured at the same sampling date. Yield were estimated by harvesting $6.6m^2$ per experimental unit and yield components were measured by sampling 10 plants per experimental unit at the harvest date. In upland soil, application of BOF slag rarely affected contents of total nitrogen, organic matter, available phosphate and potassium in soil. Soil pH, and contents of Ca and Fe in soil became higher as BOF slag rate increased. Enhancement of soil pH by application of BOF slag appeared to be closely related with increase in soil Ca content. Application rate of $2Mg\;ha^{-1}$ of lime showed almost the same effect in increase of soil Ca content as application rate of $4{\sim}8Mg\;ha^{-1}$ of BOF slag. Slag treatment hardly affected the contents of total nitrogen, $P_2O_5$, CaO, $K_2O$ and MgO in the shoot of soybean plants. Soybean plants under treatments of BOF salg showed better growth from the earlier growth stage compared with those of control treatment, and at the later growth stage, their growth was even superior to that of lime treatment. BOF slag rate of $8Mg\;ha^{-1}$ showed the highest soybean yield with $1,232kg\;ha^{-1}$. which was $330kg\;ha^{-1}$ or 37% higher than the yield of control with $902kg\;ha^{-1}$, As a result, BOF slag appeared to be useful material as a soil conditioner as well as nurient source for Ca and Fe in upland soybean fields, and its optimal rate for higher yield seemed to be around $8Mg\;ha^{-1}$.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.4
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• pp.424-429
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• 2010

To solve the problems with excessive accumulation of soil inorganic N and resulting saline soils from overuse of nitrogen fertilizer, the effect of sucrose application on decrease of soil inorganic N content and electrical conductivity (EC) was studied. Sucrose treatment greatly reduced ${NH_4}^+$-N content in soil. The amount of reduction was greater as the amount of sucrose treatment was increased. When ${NH_4}^+$-N content was reached the lowest point (about 10 mg $kg^{-1}$or lower), the C/N ratio, which determines the amount of sucrose treatment, was around 10 regardless of initial ${NH_4}^+$-N content. For the rate of ${NH_4}^+$-N reduction 15~36 hours was required to reduce the initial ${NH_4}^+$-N content to half, and 36~69 hours to lower ${NH_4}^+$-N content to the lowest point (about 10 mg $kg^{-1}$or lower). In addition, sucrose treatment greatly lowered ${NO_3}^-$-N content. In case of C/N ratio above 10, initial ${NO_3}^-$-N content of 348 mg $kg^{-1}$ was reduced to the lowest of 14~21 mg $kg^{-1}$. As for the rate of ${NO_3}^-$-N reduction by sucrose treatment, it took 36~60 hours for ${NO_3}^-$-N content to reach the lowest point for C/N ratio of 10 or higher, and it took 3 weeks, comparably longer time, for C/N ratio of 5. Lowering soil EC from sucrose treatment showed the same trend as ${NO_3}^-$-N content. As an important energy and carbon source for humankind, sugar should not be wasted and must be carefully applied to soil. In principle, the best way of preventing salt accumulation in soil is to optimize the fertilizer input. However, when over-fertilization should be dealt with, the sucrose treatment would be a possible and effective counter-measure to reduce overdosed nitrogen sources in soil.