• Korean Journal of Environmental Agriculture
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• v.18 no.1
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• pp.1-5
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• 1999

This study was conducted to investigate methane emission among rice ecotypes in paddy soil (Jeonbug series). The varieties of rice involved early maturing short-grain variety, Samcheonbyeo, middle maturing variety, Hawsungbyeo and late maturing variety, Dongjinbyeo. The seasonal change of methane flux was high from ear formation stage to heading stage. It was found that the methane flux was tended to be lower in early maturing variety than in the mid-to-late maturing variety. The plots without rice straw reduced methane emission as much as 46% relative to rice straw application. The methane emission rate through rice stem was highly correlated with temperature fluctuation. Methane emission on ecotypes by rice straw application was 0.394 g $m^{-2}day^{-1}$ in early maturing variety (Samcheonbyeo), 0.407 g $m^{-2}day^{-1}$ in mid maturing variety(Hawsungbyeo), 0.411 g $m^{-2}day^{-1}$ in late maturing variety(Dongjinbyeo).

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.1
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• pp.41-49
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• 2003

Methane emission was measured in a rice paddy under different water management and organic amendments. Methane emission from planted chambers and unplanted chambers was monitored to evaluate the rice-mediated methane emission. In flooding methane emission from planted chambers with NPK, NPK(+P), was $0.174g\;CH_4\;m^{-2}\;d^{-1}$ while that from unplanted chambers with NPK, NPK(-P), was $0.046g\;CH_4\;m^{-2}\;d^{-1}$ Methane emission from planted chambers with rice straw compost amendment, RSC(+P), was $0.214g\;CH_4\;m^{-2}\;d^{-1}$, while that from unplanted chambers with rice straw compost amendment, RSC(-P), was $0.076g\;CH_4\;m^{-2}\;d^{-1}$. Methane emission from planted chambers with rice straw amendment in Fehruary, RS2(+P), was $0.328g\;CH_4\;m^{-2}\;d^{-1}$, while that from unplanted chambers with rice straw amendment in February, RS2(-P), was $0.1g\;CH_4\;m^{-2}\;d^{-1}$. Methane emission from planted chambers with rice straw amendment in May, RS5(+P), was $0.414g\;CH_4\;m^{-2}\;d^{-1}$, while that from unplanted chamhers with rice straw amendment in May, RS5(-P), was $0.187g\;CH_4\;m^{-2}\;d^{-1}$. In intermittent irrigation methane emission from NPK(+P) was $0.115g\;CH_4\;m^{-2}\;d^{-1}$, while that from NPK(-P) was $0.041g\;CH_4\;m^{-2}\;d^{-1}$. Methane emission from RSC(+P) was $0.137g\;CH_4\;m^{-2}\;d^{-1}$, while that from RSC(-P) was $0.06g\;CH_4\;m^{-2}\;d^{-1}$. Methane emission from RS2(+P) was $0.204g\;CH_4\;m^{-2}\;d^{-1}$, while that from RS2(-P) was $0.09g\;CH_4\;m^{-2}\;d^{-1}$. Methane emission from RS5(+P) was $0.273g\;CH_4\;m^{-2}\;d^{-1}$, while that from RS5(-P) was $0.13g\;CH_4\;m^{-2}\;d^{-1}$. Methane transport via rice plant under flooding for NPK plot, RSC plot, RS2 plot and RS5 plot was 73.6%, 64.5%, 69.5% and 54.8%, respectively, and mean was 65.6%. Methane transport via rice plants under intermittent irrigation for NPK plot, RSC plot, RS2 plot and RS5 plot was 64.3%, 59.2%, 55.9% and 52.4%, respectively, and mean was 58.0%.

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.306-313
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• 2014

BACKGROUND: Forest soils contain microbes capable of consuming atmospheric methane ($CH_4$), an amount matching the annual increase in $CH_4$ concentration in the atmosphere. However, the effect of plant residue production by different forest structure on $CH_4$ oxidation is not studied in Korea. The objective of this study was to evaluate the effect of Korean alpine soils having different forestation structure on $CH_4$ uptake rates. METHODS AND RESULTS: the $CH_4$ flux was measured at three sites dominated with pine, chestnut and oak trees in southern Korea. The $CH_4$ uptake potentials were evaluated by a closed chamber method for a year. The $CH_4$ uptake rate was the highest in the pine tree soil ($1.05mg/m^2/day$) and then followed by oak ($0.930mg/m^2/day$) and chestnut trees ($0.497mg/m^2/day$). The $CH_4$ uptake rates were highly correlated to soil organic matter and moisture contents, and total microbial and methanotrophs activities. Different with the general concent, there was no any correlation between $CH_4$ oxidation rates, and soil temperature and labile carbon concentrations, irrespective with tree species. CONCLUSION: Conclusively, the methane oxidation rate was correlated in positive manner with organic matter, abundance of methanotrophs. Methane oxidation was different among tree species. This results could be used to estimate methane oxidation rate in forest of Korea after complementing information about statistical data and methane oxidation of other site.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.5
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• pp.499-509
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• 2000

Next to carbon dioxide, methane is the second largest contributor to global warming among anthropogenic greenhouse gases. Methane is emitted into the atmosphere from both natural and anthropogenic sources. Natural sources include wetlands, termites, wildries, ocean and freshwater. Anthropogenic sources include landfill, natural gas and oil production, and agriculture. These manmade sources account for about 70% of total global methane emissions; and among these, landfill accounts for approximately 10% of total manmade emissions. Solid waste landfills produce methane as bacteria decompose organic wastes under anaerobic conditions. Methane accounts for approximately 45 to 50 percent of landfill gas, while carbon dioxide and small quantities of other gases comprise the remaining to 50 to 55 percent. Using the closed enclosure technique, surface emission fluxes of methane from the selected landfill sites were measured. These data were used to estimate national methane emission rate from domestic landfills. During the three different periods, flux experiments were conducted at the sites from June 30 through December 26, 1999. The chamber technique employed for these experiments was validated in situ. Samples were collected directly by on-site flux chamber and analyzed for the variation of methane concentration by gas chromatography equipped with FID. Surface emission rates of methane were found out to vary with space and time. Significant seasonal variation was observed during the experimental period. Methane emission rates were estimated to be 64.5$\pm$54.5mgCH$_4$/$m^2$/hr from Kimpo landifll site. 357.4$\pm$68.9mgCH$_4$/$m^2$/hr and 8.1$\pm$12.4mgCH$_4$/$m^2$/hr at KwanJu(managed and unmanaged), 472.7$\pm$1056mgCH$_4$/$m^2$/hr at JonJu, and 482.4$\pm$1140 mgCH$_4$/$m^2$/hr at KunSan. These measurement data were used for the extrapolation of national methane emission rate based on 1997 national solid waste data. The results were compared to those derived by theoretical first decay model suggested by IPCC guidelines.

• Animal Bioscience
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• v.37 no.2
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• pp.173-183
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• 2024

Objective: This study aimed to evaluate whether the methane (CH₄) to carbon dioxide (CO₂) ratio (CH₄/CO₂) and methane-related traits obtained by the sniffer method can be used as indicators for genetic selection of Holstein cows with lower CH₄ emissions. Methods: The sniffer method was used to simultaneously measure the concentrations of CH₄ and CO₂ during milking in each milking box of the automatic milking system to obtain CH₄/CO₂. Methane-related traits, which included CH₄ emissions, CH₄ per energy-corrected milk, methane conversion factor (MCF), and residual CH₄, were calculated. First, we investigated the impact of the model with and without body weight (BW) on the lactation stage and parity for predicting methane-related traits using a first on-farm dataset (Farm 1; 400 records for 74 Holstein cows). Second, we estimated the genetic parameters for CH₄/CO₂ and methane-related traits using a second on-farm dataset (Farm 2; 520 records for 182 Holstein cows). Third, we compared the repeatability and environmental effects on these traits in both farm datasets. Results: The data from Farm 1 revealed that MCF can be reliably evaluated during the lactation stage and parity, even when BW is excluded from the model. Farm 2 data revealed low heritability and moderate repeatability for CH₄/CO₂ (0.12 and 0.46, respectively) and MCF (0.13 and 0.38, respectively). In addition, the estimated genetic correlation of milk yield with CH₄/CO₂ was low (0.07) and that with MCF was moderate (-0.53). The on-farm data indicated that CH₄/CO₂ and MCF could be evaluated consistently during the lactation stage and parity with moderate repeatability on both farms. Conclusion: This study demonstrated the on-farm applicability of the sniffer method for selecting cows with low CH₄ emissions.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.79-82
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• 2008

Anaerobic biodegradability(AB), which can be determined with the ultimate methane yield by the decomposition of organic materials, is one of the important parameters for the design and the operation of anaerobic digestion plant. In this study, Biochemical Methane Potential(BMP) test has been carried out to evaluate the methane yield of animal manures, such as pig and cattle slurries, and different forage crops cultivated at the reclaimed tideland, such as maize, sorghum, barley, rye, Italian ryegrass(IRG), rape, rush and sludge produced from slaughterhouse wastewater treatment plant(SWTP). In the ultimate methane yield of animal manure, that of pig slurry(no used a EM) was 407 $mlCH_4/gVS_{fed}$ higher than 242 $mlCH_4/gVS_{fed}$ of cattle slurry. The ultimate methane yield of spike-crop rye was 442.36 $mlCH_4/gVS_{fed}$ the highest among different forage crops, the other showed the value above a methane yield of 300 $mlCH_4/gVS_{fed}$. The forage crop could be used as a good substrate to improve the methane production in anaerobic co-digestion together with animal manure.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.3
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• pp.212-219
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• 2000

This study was conducted to investigate methane emission among nitrogen fertilizers in paddy soil(Jeonbug series, occurring on fluvio-alluvial plain). The application rates of rice straw was $5,000kg\;ha^{-1}$ with $110kg\;N\;ha^{-1}$ as chemical fertilizer. It was found that the methane flux tended to be lower in ammonium sulfate than in urea and latex coated urea(LCU). The seasonal variations of the methane emission flux was high during the heading stage of the rice plant. Methane concentration in the soil solution was the highest at 5cm depth, but decreased with upper and lower depth. Methane emission under rice straw application was $0.265g\;m^{-2}\;day^{-1}$ by urea application. $0.207g\;m^{-2}\;day^{-1}$ by ammonium sulfate application, $0.318g\;m^{-2}\;day^{-1}$ by latex coated urea(LCU) application while methane emission under non rice straw application was $0.192g\;m^{-2}\;day^{-1}$ by urea application, $0.165g\;m^{-2}\;day^{-1}$ by ammonium sulfate application, $0.179g\;m^{-2}\;day^{-1}$ by latex coated urea(LCU) application.

• Asian Journal of Atmospheric Environment
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• v.8 no.1
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• pp.1-14
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• 2014

Migration of methane ($CH_4$) gas from landfills to the surrounding environment negatively affects both humankind and the environment. It is therefore essential to develop management techniques to reduce $CH_4$ emissions from landfills to minimize global warming and to reduce the human risks associated with $CH_4$ gas migration. Oxidation of $CH_4$ in landfill cover soil is the most important strategy for $CH_4$ emissions mitigation. $CH_4$ oxidation occurs naturally in landfill cover soils due to the abundance of methanotrophic bacteria. However, the activities of these bacteria are influenced by several controlling factors. This study attempts to review the important issues associated with the $CH_4$ oxidation process in landfill cover soils. The $CH_4$ oxidation process is highly sensitive to environmental factors and cover soil properties. The comparison of various biotic system techniques indicated that each technique has unique advantages and disadvantages, and the choice of the best technique for a specific application depends on economic constraints, treatment efficiency and landfill operations.

• Carbon letters
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• v.17 no.1
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• pp.18-28
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• 2016

Global warming is considered one of the great challenges of the twenty-first century. In order to reduce the ever-increasing amount of methane (CH₄) released into the atmosphere, and thus its impact on global climate change, CH₄ storage technologies are attracting significant research interest. CH₄ storage processes are attracting technological interest, and methane is being applied as an alternative fuel for vehicles. CH₄ storage involves many technologies, among which, adsorption processes such as processes using porous adsorbents are regarded as an important green and economic technology. It is very important to develop highly efficient adsorbents to realize techno-economic systems for CH₄ adsorption and storage. In this review, we summarize the nanomaterials being used for CH₄ adsorption, which are divided into non-carbonaceous (e.g., zeolites, metal-organic frameworks, and porous polymers) and carbonaceous materials (e.g., activated carbons, ordered porous carbons, and activated carbon fibers), with a focus on recent research.

• Journal of Soil and Groundwater Environment
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• v.24 no.1
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• pp.24-34
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• 2019

Soil moisture regulates the fate of methane ($CH_4$) in forest soil via biological and chemical processes. The instant effect of variable precipitation on $CH_4$ uptake is, however, unclear in the forest ecosystems. Here, we measured $CH_4$ flux in a temperate forest soil immediately after variable volume of water applications equivalent to 10, 20 40, and $80mm\;m^{-2}day^{-1}$ precipitation. $CH_4$ uptake was significantly higher when the water was not applied. The $CH_4$ uptake decreased significantly with increasing water application. $CH_4$ uptake was linked with air filled porosity and water filled porosity. $CH_4$ uptake response to actual precipitation intensity was in agreement with $CH_4$ uptake results in this study. $CH_4$ uptake decreased 55% at highest precipitation intensity. Since annual $CH_4$ flux is calculated with interpolation of weekly or biweekly field observations, instant effect of precipitation can mislead the interpolated annual results.