Gentiana straminea supplementation improves feed intake, nitrogen and energy utilization, and methane emission of Simmental calves in northwest China

Xie K. L.,Wang Z. F.,Guo Y. R.,Zhang C.,Zhu W. H.,Hou F. J. 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.6

Objective: Native plants can be used as additives to replace antibiotics to improve ruminant feed utilization and animal health. An experiment was conducted to evaluate the effects of Gentiana straminea (GS) on nutrient digestibility, methane emissions, and energy metabolism of Simmental calves. Methods: Thirty-two (5-week-old) male Simmental clves, with initial body weight (BW) of 155±12 kg were fed the same basal diet of concentrates (26%), alfalfa hay (37%), and oat hay (37%) and were randomly separated into four treatment groups according to the amount of GS that was added to their basal diet. The four different groups received different amounts of GS as a supplement to their basal diet during whole experiment: (0 GS) 0 mg/kg BW, the control; (100 GS) 100 mg/kg BW; (200 GS) 200 mg/kg BW; and (300 GS) 300 mg/kg BW. Results: For calves in the 200 GS and 300 GS treatment groups, there was a significant increase in dry matter (DM) intake (p<0.01), average daily gain (ADG) (p<0.05), organic matter intake (p<0.05), DM digestibility (p<0.05), neutral detergent fibre (NDF) digestibility (p<0.05), and acid detergent fibre (ADF) digestibility (p<0.05). Dietary GS supplementation result in quadratic increases of DM intake (p<0.01), ADG (p<0.05), NDF intake (p<0.05), and ADF intake (p<0.05). Supplementing the basal diet with GS significantly increased nitrogen (N) retention (p<0.001) and the ratio of retention N to N intake (p<0.001). Supplementing the basal diet with GS significantly decreased methane (CH4) emissions (p<0.01), CH4/BW0.75 (p<0.05) and CH4 energy (CH4-E) (p<0.05). Dietary GS supplementation result in quadratic increases of CH4 (p<0.01) and CH4/DM intake (p<0.01). Compared with 0 GS, GS-supplemented diets significantly improved their gross energy intake (p<0.05). The metabolizable energy and digestive energy intake were significantly greater for calves in the 100 GS and 200 GS calves than for 0 GS calves (p<0.05). Conclusion: From this study, we conclude that supplementing calf diets with GS could improve utilization of feed, energy, and N, and may reduce CH4 emissions without having any negative effects on animal health. Objective: Native plants can be used as additives to replace antibiotics to improve ruminant feed utilization and animal health. An experiment was conducted to evaluate the effects of Gentiana straminea (GS) on nutrient digestibility, methane emissions, and energy metabolism of Simmental calves.Methods: Thirty-two (5-week-old) male Simmental clves, with initial body weight (BW) of 155±12 kg were fed the same basal diet of concentrates (26%), alfalfa hay (37%), and oat hay (37%) and were randomly separated into four treatment groups according to the amount of GS that was added to their basal diet. The four different groups received different amounts of GS as a supplement to their basal diet during whole experiment: (0 GS) 0 mg/kg BW, the control; (100 GS) 100 mg/kg BW; (200 GS) 200 mg/kg BW; and (300 GS) 300 mg/kg BW.Results: For calves in the 200 GS and 300 GS treatment groups, there was a significant increase in dry matter (DM) intake (p<0.01), average daily gain (ADG) (p<0.05), organic matter intake (p<0.05), DM digestibility (p<0.05), neutral detergent fibre (NDF) digestibility (p<0.05), and acid detergent fibre (ADF) digestibility (p<0.05). Dietary GS supplementation result in quadratic increases of DM intake (p<0.01), ADG (p<0.05), NDF intake (p<0.05), and ADF intake (p<0.05). Supplementing the basal diet with GS significantly increased nitrogen (N) retention (p<0.001) and the ratio of retention N to N intake (p<0.001). Supplementing the basal diet with GS significantly decreased methane (CH4) emissions (p<0.01), CH4/BW0.75 (p<0.05) and CH4 energy (CH4-E) (p<0.05). Dietary GS supplementation result in quadratic increases of CH4 (p<0.01) and CH4/DM intake (p<0.01). Compared with 0 GS, GS-supplemented diets significantly improved their gross energy intake (p<0.05). The metabolizable energy and digestive energy intake were significantly greater for calves in the 100 GS and 200 GS calves than for 0 GS calves (p<0.05).Conclusion: From this study, we conclude that supplementing calf diets with GS could improve utilization of feed, energy, and N, and may reduce CH4 emissions without having any negative effects on animal health.

우리나라 논에서 유기물 투입, 규산질 비료 시용, 논물관리에 따른 메탄 배출량 변화

백누리 ( Nuri Baek ),박현진 ( Hyun-jin Park ),( Pia Husna Israt ),최우정 ( Woo-jung Choi ) 한국농공학회 2022 한국농공학회 학술대회초록집 Vol.2022 No.-

메탄(CH₄)은 2019년 기준 우리나라 농축산업분야 온실가스 배출량의 50% 이상을 차지하고 있으며, 그 중 50% 정도가 담수 조건인 논 생태계에서 배출된다. 담수 상태인 논에서 CH₄은 유기물 분해에 따라 산화환원전위(Eh)가 감소하여 생성되기 때문에 토양이 호기적 상태를 유지하거나, 담수 조건에서도 유기물 분해에서 발생하는 전자(e-) 수용체가 있으면 CH₄ 발생이 감소한다. 따라서, 우리나라에서도 유기물 투입량, 논물관리, 그리고 전자수용체 유효도에 따른 CH₄ 발생량 평가 연구가 활발하게 진행되어오고 있다. 본 연구에서는 문헌조사를 통해 이와 같은 영농관리(유기물 투입, 물관리, 규산질 비료 시용)에 따른 CH₄ 배출량 변화를 종합적으로 평가하였다. 유기물 투입에 의해 CH₄ 발생량은 평균 250% 증가하였으며, 유기물 투입량과 CH₄ 발생량 사이에 정의 상관관계가 있었다. 관행 담수조건과 비교하여 간단관개나 논물얕게 대기 등 물관리에 의해 CH₄ 발생량이 평균 76% 감소하였다. 규산질 비료 투입에 의해 CH₄ 발생량이 감소하였지만, 그 정도는 13%로 물관리보다는 효과가 낮았으며, 규산질 비료 투입량 5톤 ha^-1까지는 CH₄ 발생량이 직선적으로 감소하였지만, 그 이후에는 완만하게 감소하였다. 유기물이 투입된 조건에서 논 물관리에 의해 CH₄ 발생량 저감 효과는 43%로 낮아졌다. 하지만, 유기물이 투입된 조건에서 규산질 비료 시용에 의해 CH₄ 발생량이 93% 증가하였다. 본 연구 결과는 논물관리와 규산질 비료의 CH₄ 발생량 저감 효과는 유기물 투입 여부에 따라 달라짐을 보여준다. 따라서, 향후 토양 유기물 수준이 다양한 조건에서 논물관리와 규산질 비료의 CH₄ 발생량 저감효과에 대한 연구가 필요하다.

리포솜 면역측정법을 이용한 CH50 검사의 유용성에 대한 재평가

이준,전래희,김신규 대한진단검사의학회 2021 Laboratory Medicine Online Vol.11 No.3

Background: This study aimed to evaluate whether the 50% hemolytic complement (CH50) is a suitable screening test to investigate complement activity by comparing its liposomal immunoassay-based results with C3 and C4 values and determine if it meaningfully reflects changes in the complement system. Methods: A retrospective study was conducted on 35,908 test samples that were simultaneously evaluated using C3, C4, and CH50 assays. Liposomal immunoassay was used for CH50 test, and rate nephelometry or immunoturbidimetry was used for C3 and C4 tests. The CH50, C3, and C4 results were divided into low, normal, and high groups for comparison and analysis. The distribution of C3 and C4 measurements according to the three different CH50 groups was analyzed. Results: Of the 35,908 cases, the C3 and C4 results were decreased in 19,051 (53%) and 14,666 (41%) cases, respectively. However, CH50 results were decreased in 6,257 cases (17%), which were lower than those for C3 and C4. A statistically significant difference was observed in the distribution of C3 and C4 values among different CH50 groups (P<0.001). Conclusions: The CH50 test based on the liposome immunoassay does not sensitively reflect the decrease in C3 and C4. However, it tends to show a better decrease at low concentrations proportional to the decreased amount of C3 and C4. Hence, it can be useful for severe complement deficiency screening. Therefore, there are limitations with the use of the CH50 test alone for the screening of complement activity, and care should be taken during result interpretation. 배경: 리포솜 면역측정법을 이용한 CH50 검사 결과와 C3, C4 측정치의 비교를 통해, CH50 검사가 보체의 증감을 유의하게 반영하고 있는지에 대하여 확인하고, 해당 결과를 통해 CH50 검사가 보체기능의 선별검사로서 사용하기에 적절한지 그 유용성을 평가하고자 하였다. 방법: C3, C4와 CH50 검사를 동시에 시행한 35,908건의 검사를 대상으로 후향적 연구를 시행하였다. CH50 검사는 리포솜 면역측정법으로, C3와 C4 검사는 비율비탁측정법 또는 면역혼탁측정법으로 측정하였다. CH50 결과와 C3, C4 결과를 감소, 정상, 증가군으로 나누어 비교 분석하였고, CH50 결과의 증감에 따른 C3, C4 측정치 분포를 분석하였다. 결과: 35,908건의 검사 중, C3는 19,051건(53%)에서 감소하였고, C4는 14,666건(41%)에서 감소하였다. 반면 CH50 결과는 6,257건(17%)에서 감소하여, C3와 C4의 감소율에 비해 낮았다. CH50 증가, 정상, 감소군 간에 C3와 C4 측정치 분포는 통계적으로 유의한 차이가 있었다(P<0.001). 결론: 리포솜 면역측정법에 의한 CH50 검사는 C3, C4의 감소를 민감하게 반영하지 못한다. 다만 C3, C4의 감소량에 비례하여 낮은 농도에서 더 뚜렷이 감소되는 경향을 보이므로 심한 보체결핍에서는 유용하게 사용될 수 있다. 따라서 CH50 검사를 단독으로 보체기능에 대한 선별검사로 사용하기에는 제한적이며 그 결과의 해석에 주의를 요한다.

토양 수분 변동 조건에서 시비 및 유기물 투입에 따른 CO₂와 CH₄ 방출 특성

임상선,최우정,김한용,Lim, Sang-Sun,Choi, Woo-Jung,Kim, Han-Yong 한국환경농학회 2012 한국환경농학회지 Vol.31 No.2

논 생태계를 모의하여 토양에 투입된 비료의 종류(AS, PMC, HV)와 토양 수분 변동조건(습윤기간, 전이기간, 건조 기간)으로 구분하여 $CH_4$과 $CO_2$ 플럭스를 조사하였다. $CH_4$ 플럭스는 0~13.8 mg $CH_4$/m/day의 범위에서 변화하였으 며, 시기적으로 습윤기간 초기와 전이기간과 건조기간 경계 시점에서 높은 값을 보였다. $CO_2$ 플럭스는 습윤 초기에 최대 치를 보이고 지속적으로 감소하다가 전이기간에 다시 상승하 였다. 최종토양의 탄소함량 변화는 대조구에서-5.4%이었고, 비료 처리구에서는-7.5~-16.4%이었다. HV 시용은 타 비종 에 비해 $CH_4$과 $CO_2$ 플럭스를 증가시켰는데, 이는 녹비작물 이 가축분 퇴비에 비해 상대적으로 이분해성으로 배양 초기 에 유기물 분해에 의해 $CH_4$과 $CO_2$ 발생량이 높았기 때문이 다. AS나 PMC 처리구에서 $CH_4$ 플럭스가 대조구에 비해 낮았는데, 이는 AS의 ${SO_4}^{2-}$와 퇴비에 함유된 산화형 물질($Fe^{3+}$, $Mn^{4+}$, ${NO_3}^-$)과 같은 전자 수용체에 의해 습윤기간 중 이들 물질이 전자수용체로 활용되어 $CH_4$ 생성이 감소할 수 있음 을 의미한다. PMC와 HV의 탄소 손실률을 비교하면, HV와 같은 이분해성 유기물에 비해 PMC와 같은 난분해성 유기물 의 시용이 토양 탄소량을 증가시키는 것으로 나타났다. 또한, 본 연구는 HV와 같은 녹비 작물이 질소 공급의 측면에서 화 학비료를 대체할 수 있지만, 화학비료 시용에 비해 $CH_4$ 발생 이 증가할 수 있음을 제시한다. 따라서, 이분해성 유기물(녹비 작물)과 난분해성 유기물(가축분퇴비)을 혼합 시용할 경우 양 분공급과 탄소저장량 증대에 모두 유리할 것으로 기대된다. BACKGROUND: Agricultural inputs (fertilizer and organic inputs) and water conditions can influence $CH_4$ and $CO_2$ emission from agricultural soils. This study was conducted to investigate the effects of agricultural inputs (fertilizer and organic inputs) under changing water regime on $CH_4$ and $CO_2$ emission from a soil in a laboratory incubation experiment. METHODS AND RESULTS: Four treatments were laid out: control without input and three type of agricultural inputs ($(NH_4)_2SO_4$, AS; pig manure compost, PMC; hairy vetch, HV). Fertilizer and organic inputs were mixed with 25 g of soil at 2.75 mg N/25 g soil (equivalent to 110 kg N/ha) in a bottle with septum, and incubated for 60 days. During the first 30-days incubation, the soil was waterlogged (1 cm of water depth) by adding distilled water weekly, and on 30 days of incubation, excess water was discarded then incubated up to 60 days without addition of water. Based on the redox potential, water regime could be classified into wetting (1 to 30 days), transition (31 to 40 days), and drying periods (41 to 60 days). Across the entire period, $CH_4$ and $CO_2$ flux ranged from 0 to 13.8 mg $CH_4$/m/day and from 0.4~1.9 g $CO_2$/m/day, and both were relatively higher in the early wetting period and the boundary between transition and drying periods. During the entire period, % loss of C relative to the initial was highest in HV (16.4%) followed by AS (8.1%), PMC (7.5%), and control (5.4%), indicating readily decomposability of HV. Accordingly, both $CH_4$ and $CO_2$ fluxes were greatest in HV treatment. Meanwhile, the lower $CH_4$ flux in AS and PMC treatments than the control was ascribed to reduction in $CH_4$ generation due to the presence of oxidized compounds such as ${SO_4}^{2-}$, $Fe^{3+}$, $Mn^{4+}$, and ${NO_3}^-$ that compete with precursors of $CH_4$ for electrons. CONCLUSION: Green manure such as HV can replace synthetic fertilizer in terms of N input, however, it may increase $CH_4$ emission from soils. Therefore, co-application of green manure and livestock manure compost needs to be considered in order to achieve satisfactory N supply and to mitigate $CH_4$ and $CO_2$ emission.

항온 배양 논토양 조건에서 비산재 처리에 따른 CH₄와 CO₂ 방출 특성

임상선,최우정,김한용,정재운,윤광식,Lim, Sang-Sun,Choi, Woo-Jung,Kim, Han-Yong,Jung, Jae-Woon,Yoon, Kwang-Sik 한국토양비료학회 2012 한국토양비료학회지 Vol.45 No.5

비산재 혼합에 의한 $CH_4$과 $CO_2$ 방출 저감 가능성을 조사하기 위해 질소 ($(NH_4)_2SO_4$) 무처리구와 처리구를 두고 비산재를 0, 5, 10% 수준으로 혼합한 후 토양 수분 변동조건 (습윤기간, 전이기간, 건조기간)에서 60일간 실험실내 항온배양실험을 통해 $CH_4$과 $CO_2$ flux를 분석하였다. 전체 항온배양기간 중 평균 $CH_4$ flux는 $0.59{\sim}1.68mg\;CH_4\;m^{-2}day^{-1}$의 범위였으며, 질소 무처리구에 비해 처리구에서 flux가 낮았는데, 이는 질소 처리시 함께 시용된 $SO_4^{2-}$의 전자수용체 기능에 의해 $CH_4$ 생성이 억제되었기 때문으로 판단되었다. 질소 무처리구와 처리구에서 비산재 10% 처리에 의해 $CH_4$ flux가 각각 37.5%와 33.0% 감소하였는데, 이는 물리적인 측면에서 미립질 (실트 함량 75.4%)인 비산재 시용에 의해 통기성 대공극량이 감소되어 $CH_4$ 확산 속도가 저감되었기 때문으로 판단되었다. 또한, 생화학적 측면에서는 비산재의 $CO_2$ 흡착능에 의해 $CH_4$ 생성의 주요 기작 중 하나인 이산화탄소 환원에 필요한 $CO_2$ 공급이 억제된 것도 원인 일 수 있다. 한편, 전체 항온 배양 기간의 평균 $CO_2$ flux ($0.64{\sim}0.90g\;CO_2\;m^{-2}day^{-1}$) 역시 질소 무처리구가 질소 처리구보다 높았다. 이는 일반적으로 질소 시비에 의해 토양 호흡량이 증가한다는 기존의 연구결과와는 상이한데, 본 연구에서 질소 처리에 의해 활성화된 미생물에 의해 $CO_2$ flux 최초 측정 시점 (처리 후 2일째) 이전에 이미 상당한 양의 $CO_2$가 이미 방출되어 실측 flux에 반영되지 못했기 때문으로 설명이 가능했다. $CH_4$과 유사하게 $CO_2$ flux도 비산재무처리구에 비해 비산재 10% 처리구에서 약 20% 감소하였는데, 이는 비산재의 원소 구성 중 Ca과 Mg과 토양수내 탄산이온의 탄산염 ($CaCO_3$과 $MgCO_3$)화 반응에 의한 $CO_2$ 침전 때문이다. 이상과 같은 비산재 처리에 의한 $CH_4$과 $CO_2$ flux 감소에 의해 지구온난화지수 역시 비산재 10% 처리구에서 약 20% 감소하였다. 따라서, 비산재는 논 토양에서 $CH_4$과 $CO_2$ 방출 저감에 효과가 있는 것으로 나타났으며, 실재 벼 재배 포장에서의 실험을 통한 추가적인 검증이 필요하다. To estimate potential use of fly ash in reducing $CH_4$ and $CO_2$ emission from soil, $CH_4$ and $CO_2$ fluxes from a paddy soil mixed with fly ash at different rate (w/w; 0, 5, and 10%) in the presence and absence of fertilizer N ($(NH_4)_2SO_4$) addition were investigated in a laboratory incubation for 60 days under changing water regime from wetting to drying via transition. The mean $CH_4$ flux during the entire incubation period ranged from 0.59 to $1.68mg\;CH_4\;m^{-2}day^{-1}$ with a lower rate in the soil treated with N fertilizer due to suppression of $CH_4$ production by $SO_4^{2-}$ that acts as an electron acceptor, leading to decreases in electron availability for methanogen. Fly ash application reduced $CH_4$ flux by 37.5 and 33.0% in soils without and with N addition, respectively, probably due to retardation of $CH_4$ diffusion through soil pores by addition of fine-textured fly ash. In addition, as fly ash has a potential for $CO_2$ removal via carbonation (formation of carbonate precipitates) that decreases $CO_2$ availability that is a substrate for $CO_2$ reduction reaction (one of $CH_4$ generation pathways) is likely to be another mechanisms of $CH_4$ flux reduction by fly ash. Meanwhile, the mean $CO_2$ flux during the entire incubation period was between 0.64 and $0.90g\;CO_2\;m^{-2}day^{-1}$, and that of N treated soil was lower than that without N addition. Because N addition is likely to increase soil respiration, it is not straightforward to explain the results. However, it may be possible that our experiment did not account for the substantial amount of $CO_2$ produced by heterotrophs that were activated by N addition in earlier period than the measurement was initiated. Fly ash application also lowered $CO_2$ flux by up to 20% in the soil mixed with fly ash at 10% through $CO_2$ removal by the carbonation. At the whole picture, fly ash application at 10% decreased global warming potential of emitted $CH_4$ and $CO_2$ by about 20%. Therefore, our results suggest that fly ash application can be a soil management practice to reduce green house gas emission from paddy soils. Further studies under field conditions with rice cultivation are necessary to verify our findings.

우리나라 논에서 유기물 투입, 규산질 비료 시용, 논물관리에 따른 메탄 배출량 변화

백누리 ( Nuri Baek ),박현진 ( Hyun-jin Park ),( Pia Husna Israt ),최우정 ( Woo-jung Choi ) 한국농공학회 2022 한국농공학회 학술대회초록집 Vol.2022 No.-

메탄(CH₄)은 2019년 기준 우리나라 농축산업분야 온실가스 배출량의 50% 이상을 차지하고 있으며, 그 중 50% 정도가 담수 조건인 논 생태계에서 배출된다. 담수 상태인 논에서 CH₄은 유기물 분해에 따라 산화환원전위(Eh)가 감소하여 생성되기 때문에 토양이 호기적 상태를 유지하거나, 담수 조건에서도 유기물 분해에서 발생하는 전자(e-) 수용체가 있으면 CH₄ 발생이 감소한다. 따라서, 우리나라에서도 유기물 투입량, 논물관리, 그리고 전자수용체 유효도에 따른 CH₄ 발생량 평가 연구가 활발하게 진행되어오고 있다. 본 연구에서는 문헌조사를 통해 이와 같은 영농관리(유기물 투입, 물관리, 규산질 비료 시용)에 따른 CH₄ 배출량 변화를 종합적으로 평가하였다. 유기물 투입에 의해 CH₄ 발생량은 평균 250% 증가하였으며, 유기물 투입량과 CH₄ 발생량 사이에 정의 상관관계가 있었다. 관행 담수조건과 비교하여 간단관개나 논물얕게 대기 등 물관리에 의해 CH₄ 발생량이 평균 76% 감소하였다. 규산질 비료 투입에 의해 CH₄ 발생량이 감소하였지만, 그 정도는 13%로 물관리보다는 효과가 낮았으며, 규산질 비료 투입량 5톤 ha^-1까지는 CH₄ 발생량이 직선적으로 감소하였지만, 그 이후에는 완만하게 감소하였다. 유기물이 투입된 조건에서 논 물관리에 의해 CH₄ 발생량 저감 효과는 43%로 낮아졌다. 하지만, 유기물이 투입된 조건에서 규산질 비료 시용에 의해 CH₄ 발생량이 93% 증가하였다. 본 연구 결과는 논물관리와 규산질 비료의 CH₄ 발생량 저감 효과는 유기물 투입 여부에 따라 달라짐을 보여준다. 따라서, 향후 토양 유기물 수준이 다양한 조건에서 논물관리와 규산질 비료의 CH₄ 발생량 저감효과에 대한 연구가 필요하다.

구두 발표 : 구두발표(OA) - 농업환경 및 토양,수질 분야 ; 논 토양에서 벼 품종이 메탄 방출량에 미치는 영향

제시구티어레즈 ( Jessie Gutierrez ),김상윤 ( Sang Yoon Kim ),사라루이스아툴바 ( Sarah Louise Atulba ),황현영 ( Hyun Young Hwang ),김길원 ( Gil Won Kim ),김필주 ( Pil Joo Kim ) 한국환경농학회 2013 한국환경농학회 학술대회집 Vol.2013 No.-

We assessed the effect of eight Japonica rice (Oryza sativa L.) cultivars on CH4 emission in typical mono-rice paddy soil based on our hypothesis that the CH4 flux may differ significantly among rice cultivars because each rice cultivar has different physiological and anatomical characteristics and may differently affect the microbial abundance involved in the CH4 dynamics in paddy soil. The rice cultivation experiment was conducted over 3 years (2010-2012) at the Duryang Experimental Station, Gyeongsang National University, Sacheon, South Korea. Eight cultivars selected included the late-maturing (135 days) such as Chuchung, Dongjin, Ilmi, Junam, Nampyeong, Samkwang, and early-maturing like Odae and Woonkwang cultivars. A closed chamber method (Ali et al., 2009) was used to estimate CH4 fluxes for the entire cropping periods. For determining CH4 production potentials, methanogens abundance and activity, total carbohydrates and dissolved organic C in soil and organic acids in solution solutions were analyzed. Methanotrophs abundance and activity in soil, dissolved CH4 and CO2 in soil solution as well as root oxidation area were investigated by rhizobox and digital image analysis experiment for characterizing CH4 consumption capacity. The overall patterns of CH4 emission rates were similar among the cultivars for each year. A typical CH4 emission pattern was observed, in which, CH4 emission rates were lower at the initial vegetative stage, rapidly increased with the developing anaerobic soil condition and plant growth, and peaked at the maximum heading stage of the rice plant. The CH4 emissions then rapidly returned to background levels at harvesting stage. The mean CH4 emission rates (0.15-0.37 g m-2day-1) and total CH4 fluxes (20.0-50.0 g m-2) varied significantly among the cultivars (P<0.05). Methane fluxes were directly affected by the substrate-producing potential and gas transport capacity of each cultivar rather than the external plant growth variables. With regards to CH4 production, methanogen abundances, carbohydrates and dissolved organic C in soil and total organic acids in soil solution differed significantly among the cultivars. While with regards to CH4 consumption, dissolved[CH4] and [CO2] in soil solution as well as root oxidation area differed significantly among cultivars. Methane fluxes were highly positively correlated with methanogen abundances, soil carbohydrates and dissolved organic Cs, and total organic acids in soil solutions while negatively correlated with methanotrophs abundance in soil, [CO2]-C/ [CO2 + CH4]-C in soil solution and root oxidized area, but not with any of the apparent plant growth parameters. Rice cultivar and growth stage did not have an influence on the community structures of methanogens and methanotrophs. In conclusion, the selection and development of a cultivar with lower CH4 flux may be an effective countermeasure for decreasing CH4 emissions from rice paddy soil.

벼 논에서 생우분과 우분퇴비의 시용이 메탄 배출에 미치는 영향

김상윤 ( Sang Yoon Kim ),황현영 ( Hyun Young Hwang ),정승탁 ( Sung Tak Jung ),김필주 ( Pil Joo Kim ) 한국환경농학회 2013 한국환경농학회 학술대회집 Vol.2013 No.-

Cattle manure has been widely used as an organic matter source to improve soil quality and crop productivity. Cattle manure application can supply easily available carbon (C), but increase methane (CH4) emission from rice paddy soil during cultivation. We hypothesized that applying composted manure which contained more stable and complex organic matter than fresh manure may effectively mitigate CH4 emissions in rice paddy soil during cultivation. However, the field investigation which can compare CH4 emission characteristics between fresh and composted manure applications are still limited. In order to investigate the effects of fresh and composted cow manure applications as a soil organic amendment on CH4 emission, rice yield and soil chemical properties, five treatments were installed such as NPK(no manure as control), NPK+Composted cattle manure, NPK+Fresh cattle manure, NPK+Composted dairy manure, and NPK+Fresh dairy manure at a rate of 5 Mg ha-1 based on dry weight, respectively, in a temperate mono-rice paddy field in 2011-2012. Total CH4 flux which was investigated by the closed chamber method during rice cultivation drastically increased with fresh manure additions to ca. 255-371% over the NPK treatment (269-374 kg CH4 ha-1). However, composted manure applications significantly (P<0.05) decreased seasonal CH4 flux to ca. 57-62% over fresh manure treatments (954-1268 kg CH4 ha-1). These results indicated that the increase in the stabilization of C compounds may be attributed to decrease labile C contents in composted manure applied plots, which possibly reduce CH4 emission during rice cultivation. Labile C contents in soils also showed highly positive correlation (P<0.05) with CH4 emission rates in this study. Rice productivity increased with fresh manure additions to ca. 3-22% over the NPK treatment (5.6-7.2 Mg ha-1), but more significantly improved with composted manure applications to ca. 3-25% than fresh manure treatments. As a result, the total CH4 flux per grain yield which can simultaneously compare both grain yield and greenhouse gas impact in the field studies, significantly increased with fresh manure applications (148-172 g CH4 kg-1 grain), but were not significantly different between the NPK treatment (38-67 g CH4 kg-1 grain) and composted manure treatments (47-68 g CH4 kg-1 grain). Our finding suggested that composted manure application could be a promising way to mitigate CH4 emission and to improve rice productivity in mono-rice cultivation systems.

이온교환된 Faujasite 제올라이트를 이용한 제올라이트 주형 탄소체 합성 시 이온 교환 금속과 탄소 전구체가 메탄 흡착 거동에 미치는 영향

김기준,조철희,조동우 한국청정기술학회 2024 청정기술 Vol.30 No.2

대기 중에 존재하는 저농도 CH4을 제거를 위한 흡착제 개발을 위해서 Zeolite Template Carbon (ZTC)을 합성하였다. 탄소 전구체가 ZTC 합성에 미치는 영향을 알아보기 위해서, CH4와 C2H2를 탄소 전구체로 사용하여 ZTC를 합성하였으며, 또한 이온 교환에 사용된 금속의 영향을 알아보기 위해서 CaCl2와 LiCl을 사용하여 이온교환한 Y Zeolite을 Template로사용하여 ZTC를 합성하였다. 탄소 전구체 간의 비교에서는 C2H2가 CH4 보다 더 높은 탄소 수율을 보였으며, 또한 미세기공이 발달한 ZTC를 합성하였다. 이는 C2H2의 분자 동역학적 크기(Kinetic Diameter) (3.3 Å)가 CH4의 분자 동역학적크기(Kinetic Diameter) (3.8 Å)보다 더 작기 때문에, 제올라이트 템플릿의 미세 기공 내부의 깊숙한 곳에서부터 탄소 침착을 가능하였기 때문인 것으로 판단된다. 이온 교환에 사용된 금속 전구체 간의 비교에서는 CaCl2 기반의 ZTC가 LiCl 을 기반의 ZTC보다 미세 기공이 발달한 것을 확인하였는데, 이온 교환된 Ca가 탄소 전구체에 의한 Pore Blocking을 억제해서 기공 내부로 탄소 전구체가 들어 갈 수 있게 한 덕분으로 판단된다. 합성된 ZTC를 이용하여, 298 K에서의 N2와CH4의 흡착 등온선을 측정하였는데, 전체적으로 CH4의 흡착량이 N2보다는 높다는 것을 확인하였다. 또한 CaY 기반으로 C2H2를 이용하여 합성한 ZTC 샘플이 N2와 CH4 흡착량이 가장 높았지만, 흡착 공정 설계의 중요한 인자인 CH4와 N2 의 흡착 비율 기준으론 CH4으로 합성한 샘플이 가장 높게 나왔다. 이는 N2 흡착과 관련 깊은 초미세기공이 덜 발달하여, N2의 흡착량을 줄임으로서 오히려 CH4/N2 분리도를 높게 해 주었기 때문으로 판단된다. Zeolite template carbon (ZTC) was synthesized as an adsorbent to remove low-concentration CH4 from the atmosphere. The synthesis of ZTC was performed using CH4 and C2H2 as carbon precursors and their impact on adsorption was investigated. ZTC was also synthesized using Y zeolite ion-exchanged with CaCl2 and LiCl as templates to investigate the effect of using metals in ion exchange. The comparison of the carbon precursors revealed that C2H2 had a higher carbon yield than CH4. The synthesized ZTC exhibited developed micropores due to carbon deposition deep inside the micropores of the zeolite template. The kinetic diameter of C2H2 (0.33 nm) is smaller than that of CH4 (0.38 nm), which allowed for its deposition. The study compared metal precursors used for ion exchange and confirmed that the CaCl2-based ZTC developed more micropores compared to the LiCl-based ZTC. The ion-exchanged Ca inhibited pore blocking by the carbon precursor, allowing it to enter the pores. The ability of synthesized ZTC to adsorb N2 and CH4 at 298 K was investigated. The results showed that CH4 had a higher overall adsorption amount than N2. The sample synthesized using C2H2 and CaY exhibited the highest N2 and CH4 adsorption capacity. However, the sample synthesized with CH4 had the highest CH4/N2 gas uptake ratio, which is a crucial factor in designing an adsorption process. The observed difference was likely caused by the underdevelopment of ultrafine pores that are associated with N2 adsorption. This resulted in a reduction of N2 adsorption, leading to an increase in CH4/N2 separation.

벼 재배 논토양에서 메탄의 생성 및 배출: 리뷰

권효숙,최은정,이선일,이형석,이종문,강성수 한국기후변화학회 2022 한국기후변화학회지 Vol.13 No.1

In Korea, approximately 22% of domestic methane (CH4) emissions are emitted from rice cultivation. Various studies have sought to reduce CH4 emission from rice cultivation, but studies conducted in Korea have not been reviewed. In this review, we suggest directions for research by summarizing CH4 study cases of rice paddies in Korea. In addition, we provide background information on CH4 emissions. In flooded paddies, an anaerobic environment develops; when soil redox potential reaches -200 mV, methanogens are promoted. When substrates such as acetic acid and hydrogen/carbon dioxide, which are the decomposition products of organic matter, are supplied at the optimum soil temperature of 20-40℃, CH4 emissions are accelerated. After that, 80-90% of CH4 generated from the soil is released into the atmosphere through the aerenchyma of rice. Studies have explored CH4 emissions related to various agricultural activities that affect methanogen activity in Korea. A significant number of studies have focused on the management of paddy water and organic matter in relation to increases or decreases in CH4 emissions. However, most studies were short-term evaluations of CH4 emissions. In addition, detailed analysis of the factors influencing CH4 emission was lacking in investigations focusing on the amount of CH4 emissions. Therefore, including the effects of long-term soil management on CH4 emissions, studies should be conducted a detailed part of each affecting CH4 emission factor, in future research. These results could contribute to decreasing national CH4 emissions by providing specific measures for how to strategically reduce CH4 emissions in the future.