• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.1
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• pp.41-49
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• 1994

This experiment was carried out in order to study the effect of organic fertilizer on the growth of Korean lawngrass (Zoysia matrella L. Merr.) and the change of soil chemical characteristics. The results obtained are summarized as follows : 1. Organic fertilizer was appropriate for base-dressing in the sod establishment of Korean lawngrass(Z. matrella L. Merr.) 2. Chlorophyll contents in mixed application plot of complex fertilizer(21-17-17) and organic fertilizer were more abundant than that in single application plot of organic fertilizer. 3. Application of organic fertilizer promotes the contents of available phosphorous in soil. 4. Dry weights of base-dressing and top-dressing plot had more weight about 40%, 12% than that of control plot, respectively. So base-dressing was more effective than top-dressing in the application of organic fertilizer.

• Journal of Environmental Science International
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• v.24 no.9
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• pp.1221-1231
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• 2015

The present study was conducted to find a way to recycle the coir substrate by investigating changes in its physical and chemical properties based on the number of use year. Specific gravity of unused coir substrate was $0.212g/cm^3$, while it was higher for the substrate used for 2 years. Porosity was different depending on the number of use year. The porosity of unused substrate was 51.9%, but it increased to 68.6% after used for 2 years. In general, physical and chemical properties were better in the coir substrate used for 2 years than in unused one. The number of leaves, leaf area, flesh weight and dry weight of oriental cabbage and lettuce were higher in coir substrate used for 2 years than those in unused one. Whereas, no significant difference was observed between the substrates used for one year and 2 years, indicating that the one time-used wast substrate could be recycled for cultivating vegetables. Growth of the vegetables was improved when organic fertilizer composed of complex organics with different mixing ratios was provided to the coir substrate, compared to untreated plot. The optimum mixing ratio of the wast substrate and complex organics was 2:8(v/v) for fertilization using wast coir substrate. Therefore, coir substrate generally wasted after being used for one time was reuseable by supplying organic fertilizer.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.2
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• pp.112-117
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• 2002

This study was conducted to investigate effects on the co-situs application of coated urea complex fertilizer in dry seeded rice in Dukpyong series soil. Number of spikelet established in 15 days after seeding, conventional plot was $120ea\;per\;m^2$. and whole layer placement(WLP), co-situs application 70%(CSA70%) plot and co-situs application 50%(CSA50%) plot were 146, 126 and $120ea\;per\;m^2$, respectively. There was not concentration obstacle in co-situs application plot in spite of closing application between seed and coated urea complex fertilizer. The amount of $NH_4-N$ into soil solution in different growth stage was highest in WLP 70% plot compare to other treatment. N uptaken amount was highest in CSA 70% plot as $94kg\;ha^{-1}$ compare to $90kg\;ha^{-1}$ of WLP 79% plot and $82kg\;ha^{-1}$ of CSA 50% plot. However, N use efficiency of CSA 50% plot was highest among treatments as 48%. Rice yield was highest in CSA 70% plot as 102% compared to conventional plot.

• Nuclear Engineering and Technology
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• v.11 no.1
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• pp.47-54
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• 1979

A field experiment has been carried out to evaluate the residual effect of zinc fertilizers by rice plant grown under flooded conditions in the field. The results obtained are summarized as fellows ; Residual effect of zinc fertilizers on yields of rough and hulled grains showed slight increases. Effect of zinc application methods on yields of the grains were shown that zinc mixed treatment could be more effectively utilized than treatment of zinc on the soil surface. In case of levels of zinc application, 5 kg zinc per hectare represented high yields of the grains than those obtained from 10kg and 20kg zinc placement per hectare respectively. Regarding the form of zinc fertilizers, the urea-zinc complex showed less effective on yields of the grains than did the zinc sulfate. This phenomenon was consistent with the previous result. Yields of total zinc in rice plant grown on the rice straw added soils (Treatment No. 2 and 8) and the urea-zinc complex treated soil were increased markedly as compared to those data obtained from the previous year. The percentage of zinc derived from fertilizer decreased largely as compared to that of the first year crop. The yield of fertilizer zinc in rice plant decreased slightly in the most zinc treatments but in the case of treatments of zinc mixed with the straw added soil and the urea-zinc complex increased reversely as compared to the previous results. The mixed application of zinc with soil showed higher yield of fertilizer zinc than the soil surface placement. Approximately from 4.6 to 24.3 per cent of zinc taken up by rice plants were derived from the fertilizer zinc. Zinc fertilizer use efficiency ranged from 0.213 to 0.584 per cent when 5 kg zinc per hectare applied.

• Environmental Engineering Research
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• v.23 no.1
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• pp.46-53
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• 2018

This study explores the environmentally innovative and low-impact technology, a zero food waste system (ZFWS) that utilizes food waste and converts it into composts or biofuels and curtails carbon emissions. The ZFWS not just achieves food waste reductions but recycles food waste into fertilizer. Based on a fermentation-extinction technique using bio wood chips, the ZFWS was employed in a field experiment of the system installed in a large-scale apartment complex, and the performance of the system was examined. The on-site ZFWS consisted of three primary parts: 1) a food waste slot into which food waste was injected; 2) a fermentation-extinction reactor where food waste was mixed with bio wood chips made up of complex enzyme and aseptic wood chips; and 3) deodorization equipment in which an ultraviolet and ozone photolysis method was employed. The field experiment showed that food waste injected into the ZFWS was reduced by 94%. Overall microbial activity of the food waste in the fermentation-extinction reactor was measured using adenosine tri-phosphate (ATP), and the degradation rate of organic compounds, referred to as volatile solids, increased with ATP concentration. The by-products generated from ZFWS comply with the national standard for organic fertilizer.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1073-1085
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• 2012

Soil microbial communities are immensely diverse and complex with respect to species richness and community size. These communities play essential roles in agricultural soil because they are responsible for most of the nutrient cycles in the soil and influence the plant diversity and productivity. However, the majority of these microbes remain uncharacterized because of poor culturability. Next-generation sequencing techniques have revolutionized many areas of biology by providing cheaper and faster alternatives to Sanger sequencing. Among them, amplicon pyrosequencing is a powerful tool developed by 454 Life Sciences for assessing the diversity of complex microbial communities by sequencing PCR products or amplicons. This review summarizes the current opinions in amplicon sequencing of soil microbial communities, and provides practical guidance and advice on sequence quality control, aligning, clustering, OTU- and taxon-based analysis. The last section of this article includes a few representative studies conducted using amplicon pyrosequencing.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.2
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• pp.100-104
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• 2004

This study was conducted to investigate the effect of the salinity on growth, inorganic ion content, and photosynthetic rate ($\textrm{P}^{N}$) in Korean ginseng (Panax ginseng C.A. Meyer) with complex fertilizer (CF) and NaCl concentrations. The salinity was applied to plant using NaCl and CF, and controlled an EC as 0.0, 1.0, 2.0 and 3.0 dS $\textrm{m}^{-1}$. The salinity treated three times at 35, 42 and 49 d after transplanting. The leaf area in different electrical conductivity (EC) decreased only the higher NaCl 1.0 dS $\textrm{m}^{-1}$. The root growth increased with CF and especially, it was two times higher at 3.0 dS $\textrm{m}^{-1}$ than that of control. But the root growth sharply decreased with NaCl compared to CF. The light saturation point of Korean ginseng was around 100 $\mu\textrm{mol}\;\textrm{m}^{-2}\textrm{s}^{-1}$ photosynthetically active radiation (PAR), and $\textrm{P}^{N}$ increased as CF increased but decreased with NaCl especially at the late growth stage. The $\textrm{Na}^{+}$ content in Korean ginseng increased sharply with NaCl.

• Journal of Applied Biological Chemistry
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• v.60 no.2
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• pp.173-178
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• 2017

This study was conducted to investigate the effect of pyroligneous acids on urea hydrolysis for the purpose of inhibiting ammonia volatilization during urea fertilizer application. Different types of synthetic urease inhibitors have been searched and developed, but their use is limited due to varying inhibition effects on soil urease, and environmental problems. In this study, the effect of pyroligneous acids, a natural substance, on urea hydrolysis in soil was evaluated by analyzing inhibition of urease activity. Pyroligneous acids inhibited plant urease and microbial urease activity, as well as soil urease with various urease complex. In addition, pyroligneous acids exhibited non-competitive urease inhibition effect through urease kinetics and inhibited urea hydrolysis in the soil. This study showed that pyroligneous acids treatment with urea fertilizer decreases the loss of urea fertilizer, improves the efficiency of nitrogen application on plant and reduces the amount of nitrogen fertilizers applied in soil.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.2
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• pp.122-128
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• 2001

In order to find out the effect of nitrogen fertilizers on soil pH, EC, $NO_3-N$ and lettuce growth, this study was conducted by pot experiment in plastic film house condition. The square-pot which was $42{\times}54.5{\times}22cm$ in length, width and height, respectively, was filled with two kinds of soils in different soil EC as $0.20dS\;m^{-1}$ and $1.13dS\;m^{-1}$. Seven kinds of nitrogen fertilizers (urea, potassium nitrate, calcium nitrate, ammonium nitrate, ammonium sulphate, complex fertilizer A(11-10-10) and complex fertilizer B(12-12-12)) were treated in same standard rate of nitrogen for lettuce, transplanted the six lettuce seedlings of 10 days grown per pot, and have been grown for 38~44 days with three times harvesting. Soil pH was increased with the potassium and calcium nitrate treatments and decreased with ammonium nitrate, ammonium sulphate, complex fertilzer A and B, and the pH of urea treatments was kept the same value as the pH of before experiment. The growing status of lettuce seedling were surveyed during the early period after transplanting and withering of seedling was occured in all treatments. The withering rates were 10% in soil of EC $0.20dS\;m^{-1}$ and 44% and 42% in complex fertilizer and ammonium sulphate treaments, respectively, in soil of EC $1.13dS\;m^{-1}$. $NO{_3}^-$ contents of lettuce were about $1,000{\sim}2,000mg\;kg^{-1}$ based on fresh weight and these contents were considered to be lower to compare the $NO{_3}^-$ level of EU countries.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.2
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• pp.65-70
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• 1976

The effect of leaf spray ($80{\ell}$ of 100 times diluted solution per 10a) of three liquid complex fertilizers (Compresal 1 and 2. and 3P) on rice (var, Minehikari) at 10 days before and after heading and 20 days after heading in a farmer's field was investigated by yield components and flag leaf analysis. 1. Leaf spray significantly increased filled grain ratio (at 10% level) and harvest index (at 5% level) suggesting significant yeild increase in uniform field condition. 2. Phosphorus content of flag leaf was in deficient range and increased by leaf spray while iron content was decreased indicating that liquid complex fertilizer supplied phosphorus which ratards iron translocation to the upper leaves. 3. Higher manganese content in flag leaf by leaf spray (significant at 5% level) suggests that phosphorus stimulates manganese translocation to the upper leaves resulting in favorable Fe/Mn balance. 4. Nitrogen concentration in flag leaf was in the insufficient range suggesting that nitrogen in liquid complex fertilzer had to be a nitrogen supply source. 5. In flag leaf calcium concentration was increased by leaf spray but that of boron and zinc was decreased.