• 한국대기환경학회지
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• 제20권6호
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• pp.729-738
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• 2004

Seasonal variation of major inorganic ions in the greater Seoul area was estimated using a photochemical box model and a gas/aerosol equilibrium model with emphasis on semi -volatile nitrate. Pollutant emission was determined by season by comparing the predicted concentration with the measurement one obtained for a year from the late 1996. The results showed that particulate nitrate was the highest in summer but about 40% of total nitrate was present in the gas phase. This was due to volatilization at high temperature since ammonia was sufficient to neutralize all nitrate regardless of season. As relative humidity in summer was higher than the deliquescence point, particulate ion concentration with water was two times higher than that in other season. So called ‘NOx disbenefit’ indicating increase in particulate ion concentration with decrease in NOx emission was evident especially in winter.

• 한국토양비료학회지
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• 제40권1호
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• pp.1-3
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• 2007

• 한국토양비료학회지
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• 제50권5호
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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.

• 농업과학연구
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• 제50권3호
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• pp.437-446
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• 2023

As the interest in sustainable and environmentally friendly agriculture continues to grow, there is a corresponding increase in organic fertilizers utilization. However, studies on ammonia (NH₃) emissions, which are primarily generated in the agricultural sector, by organic fertilizers are lacking. Additionally, the reliance on imported ingredients in the production of organic fertilizers hinders the widespread adoption of organic fertilizers. This study aims to evaluate NH₃ volatilization by incorporating rice husk biochar into organic fertilizers. The study also aims to assess whether domestically produced rice husk biochar can serve as a viable substitute for imported ingredients. Here, the dynamic chamber method was used under controlled conditions. Results show that inorganic fertilizers readily undergo hydrolysis, thereby rapidly generating significant amounts of NH₃, particularly in the initial stages. In contrast, organic fertilizers decompose gradually, leading to relatively long-term NH₃ emissions. The incorporation of rice husk biochar into organic fertilizers demonstrated diminished daily NH₃ emissions compared to those from commercial organic fertilizers, resulting in decreased total NH₃ volatilization. These findings show that the combination of rice husk biochar can reduce NH₃ volatilization and serve as an alternative to imported ingredients for organic fertilizers. The results of this study can be utilized as fundamental information for the assessment of biochar as a potential ingredient for organic fertilizers.

• 한국토양비료학회지
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• 제47권5호
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• pp.368-373
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• 2014

Ammonia loss from urea significantly hinders efficient use of urea in agriculture. 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. There are reports in the literature showing that the addition of zeolite to N sources can improve the nitrogen use efficiency. This study was conducted to evaluate nitrous oxide ($N_2O$) and ammonia ($NH_3$) emission by mixed treatment of urea and zeolite in upland crop field. Urea fertilizer and zeolite were applied at different rates to study their effect on $N_2O$ emission during red pepper cultivation in upland soils. The $N_2O$ gas was collected by static closed chamber method and measured by gas chromatography. Ammonia concentration was analyzed by closed-dynamic air flow system method. The total $N_2O$ flux increased in proportion to the level of N application. Emission of $N_2O$ from the field increased from the plots applied with urea-zeolite mixture compared to urea alone. But urea-zeolite mixture treatment reduced about 30% of $NH_3$-N volatilization amounts. These results showed that the application of urea and zeolite mixture had a positive influence on reduction of $NH_3$ volatilization, but led to the increase in $N_2O$ emission in upland soils.

• 한국환경농학회지
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• 제32권4호
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• pp.366-368
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• 2013

BACKGROUND: Composting is the most frequently used waste management process for animal manure in Korea's livestock industry. In the composting process, a large amount of nitrogen (N) is volatilized to the atmosphere as amonia ($NH_3$). However, quantitative information of $NH_3$ emission from composting of liquid manure is required to obtain emission factors for management of livestock manure in Korea. METHODS AND RESULTS: To evaluate the $NH_3$ emission from composting of liquid manure affected by aeration, we conducted composting of liquid pig manure with three forced aeration systems. The aeration conditions were continuous (A60), cycle of 30 min aeration and 30 min pause (A30S30) and without aeration(A0). All treatments were aerated 12 hour per day with these aeration systems. The total ratio of $NH_3$ volatilization loss to total N content in liquid manure throughout composting period was estimated to 19.9% for A0 treatment, 25.9% for A30S30 treatment and 36.3% for A60 treatment. The A30S30 and A60 aeration systems increased $NH_3$ volatilization by 30.2 and 82.3% compared with systems without forced aeration. CONCLUSION(S): Ammonia emission during liquid pig manure composting was highly affected by forced aeration. The development of liquid pig manure composting systems with forced aeration would be considered both reducing ammonia emission and efficiency of composting.

• Journal of Applied Biological Chemistry
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• 제43권2호
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• pp.86-93
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• 2000

An experiment was conducted to obtain the quantitative data on the transformation and loss of applied urea-N in waterlogged soil columns. The soil columns were pre-incubated for 35 days to develop oxidized and reduced soil conditions prior to urea application. After urea application at the rate of $150kg\;N\;ha^{-1}$(29.5 mg N), the amounts of nitrogen which were volatilized, leached, and remained in soil column were measured during 38 days of incubation period. On 2 and 4 days of incubation, 54.1%(15.9 mg N) and 98.4%(29.0mg N) of the applied urea was hydrolyzed, respectively. Most of the applied urea was completely hydrolyzed within 6 days. After urea application, the rates of ammonia volatilization were increased with the floodwater pH when the floodwater pH were higher than 7.0. The maximum rate of ammonia volatilization was $0.3mg\;d^{-1}$ when pH of the floodwater showed maximum value of 7.6. The total amount of volatilized nitrogen was 6.1% (1.8mg N) of the applied urea-N. A 63.2 % (18.6mg N) of the applied urea was remained in soil as $NH_4{^+}-N$ and 28.0% (8.2mg N) of the applied urea was leached as $NH_4{^+}-N$ at the end of the incubation. Amount of $NO_3{^-}-N$ in soil was smaller than 2.0 mg throughout the incubation period. The total amount of $NO_3{^-}-N$ leached was very small, which value was 1.8 mg. It suggested that nitrification process was not significant in waterlogged soil column of this study due to high infiltration rate of urea solution applied to the soil column. Therefore only small amount of $NO_3{^-}-N$ was lost by denitrification and leaching process.

• 한국수산과학회지
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• 제37권1호
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• pp.24-32
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• 2004

A mathematical model is used to investigate nitrogen dynamics in the intensive aquaculture ponds in the western coast of Korea. Parameters associated with water quality, sediments and growing of shrimp (Fenneropenaeus chinensis) are measured to calibrate the model for feeding ponds A and B and storage ponds. The model describes the fate of nitrogen including loadings of ammonia from feeds, phytoplankton assimilation, nitrification, sedimentation, volatilization and discharge. The model obtains good agreements with the measured values of TAN $(NH_4,\;NH_3),\;NO(NO_2,\;NO_3)$ and Chl (chlorophyll a). Impacts of water exchange on TAN and Chl are investigated, showing that the range of 0.01-0.2 (/day) cannot effectively reduce TAN but reduces Chl. Nitrogen in the ponds A is removed by sedimentation $66\%,$ volatilization $8\%,$ discharge of particulate and dissolved $8\%.$ The pond B shows $56\%\;and\;26\%$ of sedimentation and volatilization, respectively, to yield $10\%.$ decrease and 8c/o increase compared to those in the pond A. While the pond A has larger area (1.02:0.66 ha) and same stocking density (0.025 md./L) at the beginning of culture, the pond B obtains higher stocking density (0.0065:0.0091 md./L), longer feeding period (103:121 day) and resultant higher shrimp production (1.15:2.13 t/ha/cycle) at harvest. This is possibly due to the hydraulic characteristics driven by paddlewheels. At low ratio of the low speed area and the pond area, the rate of sedimentation is high, while the rate of gas exchange is low. Thus, the measurement and model analysis suggest that water quality and shrimp production are positively correlated with the hydraulic characteristics in the shrimp ponds.

• Asian-Australasian Journal of Animal Sciences
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• 제12권2호
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• pp.305-327
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• 1999

In the paper insight is given in the legislation policy to restrain environmental pollution by pig husbandry, focused on The Netherlands (Mineral Accounting System). Besides, nutritional measures are presented to reduce environmental pollution by lowering excretion of N and P, emphasizing (multi) phase feeding, the use of low protein, synthetic amino acids supplemented diets, phytase and its effect on phosphorus and calcium digestibility, its interaction with phytic acid and proteins, and the environmental impact of the use of phytase in pig diets. Also, nutritional means are indicated to reduce ammonia volatilization from pig operations. It is concluded that nutrition management can substantially contribute to reduction of N and P excretion by pigs, mainly by lowering dietary protein levels, (multi) phase feeding and the use of microbial phytase, and that the use of phytase on a large scale in The Netherlands has a tremendous environmental impact. In 20 years the excretion of P in growing-finishing pigs has more than halved. Ammonia emission from manure of pigs can be reduced substantially by lowering dietary protein content, but also by including additional non-starch polysaccharides in the diet. A very promising method to reduce ammonia emission is to manipulate dietary cation-anion difference, e.g. by adding acidifying salts to the diet, which will lower pH of urine substantially. Further research is desirable. This also applies to determining dietary factors influencing the odour release from manure. Finally, some speculation on the future of pig farming from an environmental viewpoint is presented.

• Korean Chemical Engineering Research
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• 제45권2호
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• pp.133-142
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• 2007

화학비료의 과다사용으로 환경오염의 문제가 심각해 지면서 친환경 농자재(목초재 또는 축산분뇨 등)를 사용하는 유기농업의 필요성이 대두되어 왔다. 이러한 친환경 농자재의 시용량은 작물 종류별, 토양 종류별, 계절별, 재배환경 등에 따라 결정되어져야 한다. 유기비료로서 축산분뇨량의 효율적 사용과 축산분뇨로부터의 암모니아 방출량 저감을 위해서는 먼저 축산분뇨의 경작지 시비 후 암모니아 방출모델이 제시되어야 한다. 그리고 암모니아 방출에 영향이 큰 인자들을 찾아내어 이 인자들을 변화시킴으로서 암모니아 방출량을 감소시킬 수 있을 것이다. 이 연구에서는 인공신경망(artificial neural network) 기법을 이용하여 시비된 돈분의 암모니아 휘산량을 예측한다. 유럽지역에서 얻은 암모니아 방출 실험데이터(ALFAM database)를 바탕으로, 암모니아 손실 영향인자에 따른 암모니아 방출량을 Michaelis-Menten 모델식을 이용하여 예측한다. 이 모델식의 모델인자(암모니아 최대 방출량과 암모니아 최대 방출량의 50%에 도달하는 시간)는 feedforward-backpropagation 인공신경망 기법으로 예측하였고, 가중치 분할법(weight partitioning method)으로 암모니아 손실에 미치는 총 15개의 영향인자의 상대적인 중요도를 분석하였다. 그 결과 암모니아 방출량은 기후에 따라 크게 좌우되고, 돈분의 상태도 상당한 영향을 주고 있다.