• 한국환경농학회지
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• 제37권3호
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• pp.172-178
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• 2018

BACKGROUND: Composted animal manure applied to the arable soil for improving soil quality and enhancing crop productivity causes greenhouse gas emissions such as nitrous oxide ($N_2O$) by processes of nitrification and denitrification. However, little studies have been conducted on determining effect of application ratio of composted animal manure on $N_2O$ emission rate and its annual emission pattern from upland soil in South Korea. Therefore, this study was conducted to determine $N_2O$ emission rate and its annual emission pattern from upland soil supporting for sweet potato. METHODS AND RESULTS: Composted animal manure was applied at the ratio of 0, 10, and 20 Mg/ha to an upland soil supporting for sweet potato (Ipomoea batatas). Nitrous oxide emission was examined during growing season and non-growing season from May 2016 through May 2017. Daily $N_2O$ fluxes showed peaks right after applications of composted animal manure and inorganic nitrogen fertilizer. Precipitation and soil water content affected daily $N_2O$ flux during non-growing season. Especially, $N_2O$ flux was strongly associated with water filled pore space (WFPS). We assumed that the majority of $N_2O$ measured during growing season of sweet potato was produced from nitrification and subsequent denitrification. Annual cumulative $N_2O$ emission rate significantly increased with increasing application ratio of composted animal manure. It increased to 12.0 kg/ha/yr from 8.73 kg/ha/yr at control with 10 Mg/ha of composted animal manure and to 14.0 kg/ha/yr of $N_2O$ emission with 20 Mg/ha of the manure. CONCLUSION: To reduce $N_2O$ emission from arable soil, further research on developing management strategy associated with use of the composted animal manure and soil moisture is needed.

• Membrane and Water Treatment
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• 제9권2호
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• pp.123-128
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• 2018

Common aquaculture practices include the use of certain pharmaceuticals such as antibiotics in avoiding diseases and promoting a healthier growth of the culture. The aim of this study is to monitor and assess the influence of different low oxytetracycline concentrations on the transformation of nitrogen compounds under aeration condition in a lab-scale recirculating aquaculture system (RAS). Over $1mg\;L^{-1}$ dose of oxytetracycline to aquaculture had induced ammonia($NH_4-N$), nitrate($NO_3-N$), soluble COD accumulation in RAS. In addition, nitrous oxide ($N_2O$) emission from RAS was significantly reduced during the oxytetracycline dose periods. After ceasing the dose of oxytetracycline, ammonia oxidation and nitrous oxide re-emission were observed. This observation indicated that low concentrations of oxytetracycline could affect the nitrogen species in RAS. Also, the emission mechanisms of $N_2O$ may not be only dependent on nitrification process but also dependent on denitrification process in our RAS system.

• 한국토양비료학회지
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• 제19권1호
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• pp.76-82
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• 1986

1. 항온기간중(恒溫期間中) $N_2O$의 경시적(徑時的) 발생량(發生量)은 항온(恒溫) 1일(日)과 10일경(日傾) 그리고 $N_2$의 발생량(發生量)은 1일(日)과 30일경(日傾)에 많았다. 2. 토양유기물함량별(土壤有機物含量別) 탈질량(脫窒量)은 현저(顯著)한 차이(差異)를 보이지 않았으며 시용유기물간(施用有機物間)에는 녹비(綠肥)>볏짚>퇴비(堆肥)>무시용(無施用)의 순서(順序)로 높았다. 3. 질소시비량(窒素施肥量)이 증가(增加)할수록 탈질량(脫窒量)은 증가(增加)되었으나 토양간(土壤間)에는 뚜렷한 차이(差異)가 없었음. 4. 탈질반응속도(脫秩反應速度)(계수(係數))는 토양유기물함량(土壤有機物含量)이 많고 역분해성유기물(易分解性有機物)을 시용(施用)할수록 증가(增加)되었음. 5. 토양중(土壤中) 탄소발생량(炭素發生量)과 탈질량(脫窒量)과의 관계(關係)에서 아산화질소(亞酸化窒素)는 정상관(正相關) 그리고 분자상질소(分子狀窒素)는 부상관관계(負相關關係)를 보였음. 6. 탄소(炭素) 1 mg이 소모(消耗)될때 약 4 mg의 $N_2O$와 3 mg의 $N_2$가 생성되었음.

• Asian Journal of Atmospheric Environment
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• 제9권3호
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• pp.187-193
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• 2015

Livestock is one of the major contributors of greenhouse gases (GHGs). It accounts for 14.5% of the global GHGs emissions like methane ($CH_4$) from enteric fermentation and manure, nitrous oxide ($N_2O$) from manure and fertilizer. Since enteric emissions are a major contributor of $CH_4$ than that of manure emissions hence primary efforts were made on reducing enteric emissions, with minor attention to dung emissions. Many researches were conducted by dietary manipulation to mitigate enteric $CH_4$ emission. However dietary manipulation also had significant effects on manure GHGs emissions too. Several works proved that manure $CH_4$ emissions were increased with high level of concentrate supplementation despite reduction in enteric $CH_4$. Fat and CP content of the diet has shown inconsistent results on manure $CH_4$ emissions. Amount of concentrate in the diet has shown little effect whereas dietary CP content exhibited conflicting effects on manure $N_2O$ emissions.

• 한국대기환경학회지
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• 제20권6호
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• pp.749-758
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• 2004

Nitrous oxide ($N_2$O) has been known as an important trace gas due to the greenhouse gas and the major source of stratospheric oxide of nitrogen (NO). Soil is the major source of $N_2$O in nature. The physicochemical characteristics of soils affect the emission of $N_2$O from soil. These physicochemical parameters are soil moisture, soil temperature, and soil N content. Since these parameters are correlated to the flux of $N_2$O from soil individually and compositely, there still remain many unknowns in the mechanism to produce $N_2$O in soil and the roles of such physicochemical parameters which affect the soil $N_2$O emission. Soil $N_2$O fluxes were measured at different levels in water filled pore space (WFPS), soil temperature and soil N contents from the same amounts of soils which were sampled from agriculturally managed upland field in a depth of ～30 cm at Kunsan. The soil $N_2$O flux measurements were conducted in a laboratory with a closed flux chamber system. The optimum soil moisture and soil temperature were observed at 60% of WFPS and ～13$^{\circ}C$. The soil $N_2$O flux increased as soil N contents increases during the whole experimental hours (up to 48 hours). However, average $N_2$O flux decreased after ～30 hours when organic carbon was mixed with nitrogen in the sample soils. It is suggested that organic carbon could be important for the emission of $N_2$O, and that the ratio of N to C needs to be identified in the process of $N_2$O soil emission.

• 한국기후변화학회지
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• 제8권1호
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• pp.31-39
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• 2017

The emission quantity of nitrous oxide is second largest among non-$CO_2$ greenhouse gas in Korea. In this study, we investigated loss rate of nitrous oxide which was filled in PVF and Al-PE bag as time goes on. Concentrations of tested samples were about 25 ppmv, 50 ppmv, 75 ppmv prepared by standard reference gas. In case of all experiments, loss rate of PVF bag was higher than Al-PE bag. After 18 days, loss rate of PVF bag was from 29.7% to 38.6% while Al-PE bag was from 21.7% to 23.7%. Especially the differential growed bigger when initial concentration of $N_2O$ in PVF bag was lower. And we also studied the effect of cock opening/closing procedures on loss rate. Prepared samples in experimental group were analyzed several times for 20 days and samples in control group were analysed only 1 time after 20 days. The experimental results showed that cock opening/closing procedures appeared to have little impact on loss rate.

• 한국환경농학회지
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• 제21권2호
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• pp.136-143
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• 2002

물관리방법을 달리한 상시담수와 간단관개에서 메탄과 아산화질소의 배출 양상과 서로 다른 종류의 유기물원 및 질소비료 시용에 따른 메탄과 아산화질소 배출을 비교하고 저감할 수 있는 방법을 찾기 위해 본 시험을 실시하였다. 물관리 방법으로는 상시담수 (이앙$\sim$출수 35일까지 담수)와 이앙 35일 이후 중간낙수한 간단관개 (중간낙수기간 20일), 그리고 시비방법으로는 토양을 검정한 시비량인 토양검정, 토양 검정시비량+볏짚, 돈분액비, LCU 완효성비료, 그리고 N을 시용하지 않은 대조구 등을 처리하여 메탄 및 아산화질소 배출량을 측정하였다. 메탄 배출량은 간단관개보다 상시담수께서 높았고, 아산화질소 배출량은 이와 반대로 나타났다. 유기물과 비료시용 종류에 따른 메탄과 아산화질소 배출량은 액비와 검정시비+볏짚시용구에서 가장 높았으며, LCU 완효성비료구에서 가장 낮았다. 지구온난화잠재력으로 환산한 온실가스 배출은 물관리 조건에서 상시담수가 간단관개보다 170$\sim$208% 높았으며, 요소를 시용하고 상시담수를 기준 한 것과 간단관개로 물관리하여 각 처리에 따라 온실가스 배출을 비교하면, 요소는 41.4%, LCU 완효성비료 55.8%로 온실가스 배출을 줄일 수 있는 것으로 나타났다. 그리고 비료이용효율은 LCU 완효성비료, 액비>검정시비+볏짚>검정시비 순이었다.

• 한국환경농학회지
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• 제38권4호
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• pp.245-253
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• 2019

BACKGROUND: Weathering of bottom ash (BA) might induce change of its surface texture and pH and affect physical and chemical properties of soil associated with greenhouse gas emission, when it is applied to the arable soil. This study was conducted to determine effect of weathering of BA in mitigating emission of greenhouse gases from upland soil. METHODS AND RESULTS: In a field experiment, methane (CH₄), carbon dioxide (CO₂), and nitrous oxide (N₂O) emitted from the soil was periodically monitored using closed chamber. Three month-weathered BA and non-weathered BA were applied to an upland soil at the rates of 0, 200 Mg ha^-1. Maize (Zea mays L.) was grown from July 1_st to Oct 8_th in 2018. Both BAs did not affect cumulative CH₄ emission. Cumulative CO₂ emission were 23.1, 19.8, and 18.8 Mg/ha/100days and cumulative N₂O emission were 35.8, 20.9, and 17.7 kg/ha/100days for the control, non-weathered BA, and weathered BA, respectively. Weathering of BA did not decrease emission of greenhouse gases significantly, compared to the weathered BA in this study. In addition, both BAs did not decrease biomass yields of maize. CONCLUSION: BA might be a good soil amendment to mitigate emissions of CO₂ and N₂O from arable soil without adverse effect on crop productivity.

• 한국기후변화학회지
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• 제8권4호
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• pp.347-355
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• 2017

Methane and nitrous oxide are main greenhouse gases from agricultural system and their global warming potential are 25 and 258 times stronger than that of $CO_2$, respectively. In 2016, the emission was $21,290Gg\;tone\;CO_2-eq$. which was emitted from agriculture sector and about 3.1% of total GHG emission of Korea. Those guidelines that were published by IPCC have methodology for GHGs emission calculation as well as emission factor and so on. For recent 5 years, GHGs emissions in Korea have calculated by MRV which has been improved every year based on IPCC guidelines. Analysis as estimating method improvement showed that the methane emissions from rice cultivation were the lowest on 2012 methodology, and the highest on 2014 methodology. On the other hand, the emissions of agricultural soils were the lowest on 2015 methodology and the highest on 2012 methodology. Total emissions from agriculture sector were the lowest on 2015 methodology and the highest on 2012 methodology. Compared with 2016 methodology, the GHGs emitted as few as $-1,865Gg\;tone\;CO_2-eq$ and as many as $2,717Gg\;tone\;CO_2-eq$. GHGs emissions can vary greatly, depending on how to use the emission factor and activity data. Therefore, it need constantly a detailed analysis for methodology and GHGs emission in the future.

• 환경위생공학
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• 제9권1호
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• pp.62-66
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• 1994

Nitrous Oxide( NaO), one of the green house gases, is not confirmed it's sources, sinl life time in the atmosphere clearly so far, In this paper, the emission sources physical characteristics, concentration in the air, monitoring method and distribution for the global warming gas were summarized.