• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.105-110
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• 2011

BACKGROUND: In this study, 5 different treatments such as non-treatment, mixed expeller cake 1.0 N (standard nitrogen fertilizer), rice straw, rice straw+mixed expeller cake 0.5 N, rice straw+mixed expeller cake 1.0 N were performed over 4 cropping seasons over 2 years in order to identify the optimal application rate of mixture of rice straw and mixed expeller cake, organic source in organic cultivation of tomatoes. METHODS AND RESULTS: There was no difference in all treatments in case of 200 mg/kg in the nitrate nitrogen content in soil prior to the first cropping season test under the criteria for nitrogen nutrient based on yield of crops, cultivation without fertilizers seems possible. But in the second cropping season, no treatment and rice straw showed the reduction of yield and in the third cropping season, rice-straw+mixed expeller cake 0.5 N treatment showed the significant difference. The content of nitrate nitrogen in soil prior to cropping seasons was evaluated in 160 mg/kg and standard fertilization such as mixed expeller cake, source of nitrogen, are needed due to the deficiency of nitrogen. In terms of application of organic resources, rice straw showed the effects of improvements on physical properties of soil such as bulk density, cation exchange capacity and humus contents, but the mixed expeller cake did not show any significant differences in improvements on physical properties of soil. CONCLUSION(s): Fertilizer management in organic cultivation of tomatoes is thought to produce the reliable quantity of crops as well as keep the high quality of soils by using the optimal application rate of mixed expeller cake according to the contents of nitrate nitrogen in soil and rice straw which improves the physical properties of soil.

• Journal of the Korean Society of Industry Convergence
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• v.5 no.3
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• pp.213-218
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• 2002

Total nitrogen is a major pollutant which mostly causes eutrophication and red tide. Wastewater effluent from printing of cotton-viscose rayon containing high concentrations of total nitrogen can not be effectively treated with a typical biological treatment process. This paper provides a new treatment process and experimental results for the removal of high strength nitrogen from dyeing wastewater. The optimum conditions of air stripping for the removal of total nitrogen include around pH 12, temperature $60^{\circ}C$ with 60 minutes of stripping time. In case of a filtration-air stripping process, an initial level ($500mg/{\ell}$) of total nitrogen was significantly reduced to below $60mg/{\ell}$. Deconite was synthesised for further decomposition of organic nitrogen. Thus, a filtration-decomposition-air stripping process was possibly achieved, by which a high level ($900mg/{\ell}$) of total nitrogen was effectively removed to below $60mg/{\ell}$ P. Finally, a continuous new process for the removal of total nitrogen is proposed and confirmed, based on batch experimental results, and its process validity is further discussed throughout.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.1
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• pp.1-3
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• 1999

This study was carried out to determine the effects on rice growth, yields and soil improvement under the different nitrogen levels in machine-transplanted rice after plowing at the fruiting stage of milk vetch. The fresh weight of milk vetch at plowing time was 20.95 ton/ha. In dry weight, T-N and C/N were 1.58%, 21.8%, respectively. Organic matter, total nitrogen and exchangeable calcium of soil after the experiment in the plot of milk vetch were higher than those before the experiment. Leaf area and dry weight of rice plants at heading date increased as nitrogen level increased. The number of panicle and spikelets per $\textrm{m}^2$were not different except for the 110 kg/ha nitrogen level plot with milk vetch. Brown rice yield ranged from 5.45 to 6.08 ton/ha, in creasing with increased nitrogen level. So the yield increased by 1% at 77 kg/ha nitrogen level, 7% at 110 kg/ha nitrogen level plot with milk vetch compared with conventional level (rice straw 5.4 ton/ha and nitrogen 110 kg/ha).

• Applied Biological Chemistry
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• v.27
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• pp.56-67
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• 1984

As in many other country, the use of organic matter in Korea has long history. Farmers understand the value of organic matter as the source of plant nutrient and soil improving agent in general. Since 50 years ago, the sources of organic matter in paddy soils were compost, rice and barly straw, green manure, animal waste, fish and beancake, etc.. Application of green manures such as vetch and chinese milk vetch showed no significant effect on the yield of brown rice in paddy soil. On the other hand, the effects of compost and rice straw showed more significant on the yield of brown rice in paddy soil. Application of rice straw in rice cultivation is commonly made at different times between harvest, early spring and several weeks before transplanting. Considering the suitable paddy soil for application of rice straw under well to moderately well drained soil, the yield was pronounced more than poorly drained soil. Based on laboratory and field experimants, application of rice straw promoted the decrease of oxidation-reduction potential in well to moderately well drained soil. This results to be enhanced the release of some mineral nutrients,. such as potassium, calcium, silicon, and increase of availability of soil phosphorus. In the field experiments, results obtained from nitrogen fraction on the immobilization-mineralization of the tracer nitrogen applied in paddy soil,the amount and index of organic nitrogen incoporated in soil was more pronounced in rice straw application than control. Rice straw and its transformation products incoporated in the soil, provided the inflow of energy necessary to maintain heterotrophic microbes activities. Rice straw and its transformation products, especially soluble carbohydrate, enhanced the population of free-living heterotrophic $N_2$ - fixing microbes. Moreover, rice straw and its transformation products in paddy soil, enhanced the activities of soil enzymes such as dehydrogenase and urease.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.5
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• pp.325-335
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• 2017

This study was carried out for 30 days in aeration type and agitation type reactor to characterize organic matter decomposition and ammonia volatilization during the liquid composting of pig slurry, and organic matter and nitrogen removal rate through mass balance analysis was analyzed. In the aeration type reactor, the pH increased from 7.0 to 9.13, and TS 34.5%, VS 33.4%, $BOD_5$ 71.2%, $COD_{Cr}$ 62.3% and TOC 83.2% were removed. In addition, 44.6% of TN and 65.0% of ${NH_4}^+-N$ were removed. In the agitation type reactor, the pH increased from 7.0 to 8.10, and the removal rates of TS 0.9%, VS 0.5%, $COD_{Cr}$ 27.5%, $BOD_5$ 28.9% and TOC 41.3% were obtained. And TN and ${NH_4}^+-N$ showed removal rate of 25.3% and 29.2%, respectively. The first order kinetics constant related to $BOD_5$ degradation was $-0.039day^{-1}$ for aerobic liquid composting and $-0.013day^{-1}$ for agitated reactor. Nitrogen loss in aerobic liquid composting was about 2.3 times higher than that of agitated reactor, whereas FAN/TAN in aerobic liquid composting was about 7.9 times higher than that of agitation type reactor. Therefore, despite the low FAN/TAN in the agitation type reactor, the nitrogen loss rate was relatively high.

• Korean Journal of Medicinal Crop Science
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• v.27 no.1
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• pp.1-8
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• 2019

Background: This study was conducted to investigate the effects of fertilization with the application of mixed organic matter after cultivating green manure crops on the growth and saponin content of Codonopsis lanceolata Trautv. Methods and Results: Five type of cultivation of green manure crops were done: hairy vetch as a single seedling crop (HV), hairy vetch and rye as a mixture of seedling (HV/R), additional fertilization with mixed organic matter after cultivation of a seedling mixture (HV/R/MO), chemical fertilizer (CF), and a non-treated control (NT). The total nitrogen content was the highest in the HV/R/MO treatment, followed by the HV, CF, HV/R and NT treatments, respectively. Nitrogen fixation was higher in the single seedling treatment with hairy vetch (HV) than in the treatment with a mixture of hairy vetch and rye seedling (HV/R). Moreover, the growth of C. lanceolata was greatly increased by the application of additional fertilizer after treatment with the mixture of hairy vetch and rye seedlings. The HV/R/MO treatment produced the highest total lancemaside content among the treatments, followed by HV, HV/R, CF, and NT, respectively. Conclusions: It was verified that C. lanceolata experienced superior growth with the application of mixed organic matter as additional fertilizer after the cultivation of green manure crops, and the content of its major saponins, lancemasides were also increased by this treatment.

• Journal of Microbiology and Biotechnology
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• v.10 no.4
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• pp.455-461
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• 2000

Abstract Spirulina platensis was grown in SWlUe waste to reduce inorganic compowlds and simultaneously produce feed resources. Spirulina platensis prefers nitrogenous compounds in Ibe order: $NH_4^{+}-N>NO_3^{-}-N>simple-N$ such as urea and simple amino acids. It even consumes $NH_4^{+}-N$ first when urea or nitrate are present. Therefore, the content of residual $NH_4^{+}-N$ in Spimlina platensis cultures can be determined by the relative extent of the following processes: (i) algal uptake and assimilation; (ii) ammonia stripping; and (iii) decomposition of urea to NH;-N by urease-positive bacteria. The removal rates of total nitrogen ffild total phosphorus were estimated as an indicator of the treatment effIciency. It was found that Spirulina platensis was able to reduce 70-93% of $P_4^{3-}-P$, 67-93% of inorganic nitrogen, 80-90% of COD, and 37-56% of organic nitrogen in various concentrations of swine waste over 12 days of batch cultivation. The removal of inorganic compounds from swine waste was mainly used for cell growth, however, the organic nitrogen removal was not related to cell growlb. A maximum cell density of 1.52 dry-g/l was maintained with a dilution rate of 0.2l/day in continuous cultivation by adding 30% swine waste. The nitrogen and phosphorus removal rates were correlated to the dilution rates. Based on the amino acid profile, the quality of the proteins in the Spirulina platensis grown in the waste was the same as that in a clean culture.ulture.

• Journal of Environmental Analysis, Health and Toxicology
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• v.21 no.4
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• pp.229-236
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• 2018

In this study, inter-laboratory comparison was done using elemental analyzer-isotope ratio mass spectrometers (EA-IRMSs) to determine carbon and nitrogen contents as well as stable carbon and nitrogen isotopic compositions (${\delta}^{13}C$ and ${\delta}^{15}N$) of five environmental samples containing lake and marine sediments, higher plant leaves, and fish muscle, and one organic analytical standard (Protein (Casein) Standard OAS). Five national laboratories participated in this comparison study, and each laboratory analyzed all five samples and the analytical standard. Results showed that variations in total organic carbon (TOC) and total nitrogen (TN) contents as well as ${\delta}^{13}C_{TOC}$ and ${\delta}^{15}N_{TN}$ values among the laboratories were large compared to the analytical uncertainties. The results highlighted the inhomogeneity of the test samples and thus, the need to select suitable standard reference materials for future inter-laboratory studies. Further inter-laboratory comparison exercises could promote good measurement practices in the acquisition of stable carbon and nitrogen isotopic composition data.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.1
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• pp.14-20
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• 2006

In this study, the feasibility of simultaneous removal of organic materials and nitrogen in the waste-water from fisheries processing plant was evaluated using entrapped mixed microbial cell technique(EMMC) process. The experiment was performed using activated sludge from municipal sewage treatment plant which was immobilized with gel matrix by cellulose triacetate. It was found that the stable operation at the treatment system which is composed of anoxic and oxic tank, was possible when the organic and nitrogen loading rates were increased stepwise. The organic and nitrogen loading rates were applied from 0.65 to $1.72kgCOD/m^3/d$ and from 0.119 to $0.317kgT-N/m^3$ with four steps, respectively. The maximum nitrogen loading rate which could satisfy the regulated effluent standard of nitrogen concentration, was $0.3kgT-N/m^3/d$. The removal efficiency of total nitrogen was decreased apparently as increasing nitrogen loading rates, whereas the removal efficiency of ammonium nitrogen was effective at the all tested nitrogen loading rates. Therefore, it was concluded that nitrification was efficient at the system. Nitrate removal efficiency ranged from 98.62% to 99.51%, whereas the nitrification efficiency at the oxic tank ranged 94.0% to 96.9% at the tested loading rates. The removal efficiencies of chemical oxygen demand(COD) and those of total nitrogen at the entire system ranged from 94.2% to 96.6% and 73.4% to 83.4%, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.2
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• pp.123-130
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• 2000

This study was carried out to examine the effects of animal manure on efficiency of the nitrogen utilization of silage corn (Zea mays L.) and soil fertility. The experiment was conducted on the field plot at Gongiam, Kwangju, Kyunggi-Do for 3 years, from 1996 to 1998, and arranged in split-plot design with three replications. The main plots were two kinds of composts such as swine manure fermented with sawdust (SMFWS) and swine manure fermented without sawdust (SMF). Subplots were the nitrogen fertilization rate (0, 100, 200, 300 and 400kgNhalyear). The nitrogen (N) yield increased as the nitrogen fertilization rate increased up to a rate of 300 kg Nha, but decreased at rate of 400 kg Nlha. Nitrogen yield in SMF treatments was higher than that of SMFWS treatments. But there were no significant differences between SMFWS and SMF treatments. Organic matter (OM) content of the soils in SMFWS was higher than that of SMF, &d was not significantly different between SMFWS and SMF treatments. OM content increased with increasing the nitrogen fertilization rate. Total nitrogen (TN) content of the soils increased as the nitrogen fertilization rate increased. No difference of TN content was found between SMFWS and SMF treatments. (Key words : Swine manure, Compost, Corn, Sawdust, Nutritive value)