• Journal of Animal Science and Technology
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• v.61 no.3
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• pp.122-137
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• 2019

Methane, one of the important greenhouse gas, has a higher global warming potential than that of carbon dioxide. Agriculture, especially livestock, is considered as the biggest sector in producing anthropogenic methane. Among livestock, ruminants are the highest emitters of enteric methane. Methanogenesis, a continuous process in the rumen, carried out by archaea either with a hydrogenotrophic pathway that converts hydrogen and carbon dioxide to methane or with methylotrophic pathway, which the substrate for methanogenesis is methyl groups. For accurate estimation of methane from ruminants, three methods have been successfully used in various experiments under different environmental conditions such as respiration chamber, sulfur hexafluoride tracer technique, and the automated head-chamber or GreenFeed system. Methane production and emission from ruminants are increasing day by day with an increase of ruminants which help to meet up the nutrient demands of the increasing human population throughout the world. Several mitigation strategies have been taken separately for methane abatement from ruminant productions such as animal intervention, diet selection, dietary feed additives, probiotics, defaunation, supplementation of fats, oils, organic acids, plant secondary metabolites, etc. However, sustainable mitigation strategies are not established yet. A cumulative approach of accurate enteric methane measurement and existing mitigation strategies with more focusing on the biological reduction of methane emission by direct-fed microbials could be the sustainable methane mitigation approaches.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.1
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• pp.38-46
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• 2005

This study was carried out to quantify the rates of anaerobic mineralization and sulfate reduction, and to discuss the potential effects of benthic fauna on sulfate reduction in total anaerobic carbon respiration in Ganghwa intertidal flat in Korea. Anaerobic carbon mineralization rates ranged from 26 to 85 mmol $C\;m^{-2}\;d^{-1}$, which accounted for approximately 46 tons of daily organic matter mineralization in the intertidal flat of southern part of the Ganghwa Island (approximately $90\;km^2$). Sulfate reduction ranged from 22.6 to 533.4 nmol $cm^{-3}\;d^{-1}$, and were responsible for $31{\sim}129%$ of total anaerobic carbon oxidation, which indicated that sulfate reduction was a dominant pathway for anaerobic carbon oxidation in the study area. On the other hand, the partitioning of sulfate reduction in anaerobic carbon mineralization in October decreased, whereas concentrations of Fe(II) in the pore water increased. The results implied that the re-oxidation of Fe(II) in the sediments is stimulated by macrobenthic activity, leading to an increased supply of reactive Fe(II), and thereby increasing Fe(III) reduction to depress sulfate reduction during carbon oxidation.

• Bulletin of the Korean Chemical Society
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• v.23 no.7
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• pp.990-994
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• 2002

Hydroxybenzothiophenes, dihydroxy-benzothiophenes, and benzothiophenedione were identified as inter-mediates of benzothiophene (BT) exposed to ultrasonic irradiation. It is proposed that benzothiophene is oxidized by OH radical to sequentially for m hydroxybenzothiophenes, dihydroxybenzothiophenes, and benzothiophenedione. Benzothiophene is decomposed rapidly following pseudo-first-order kinetics in a first-order manner by ultrasonic irradiation in aqueous solution. The toxicity of sonochemically treated solutions was checked by E. coli and a less inhibition in bacterial respiration was observed from the 120-min treated benzothiophene sample than from the untreated benzothiophene sample. Also evolution of carbon dioxide and sulfite was observed during ultrasonic reaction. A pathway for ultrasonic decomposition of benzothiophene in aqueous solution is proposed.

• The Plant Pathology Journal
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• v.40 no.2
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• pp.99-105
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• 2024

Land plants produce glucose (C₆H₁₂O₂) through photosynthesis by utilizing carbon dioxide (CO₂), water (H₂O), and light energy. Glucose can be stored in various polysaccharide forms for later use (e.g., sucrose in fruit, amylose in plastids), used to create cellulose, the primary structural component of cell walls, and immediately metabolized to generate cellular energy, adenosine triphosphate, through a series of respiratory pathways including glycolysis, the tricarboxylic acid cycle, and oxidative phosphorylation. Additionally, plants must metabolize glucose into amino acids, nucleotides, and various plant hormones, which are crucial for regulating many aspects of plant physiology. This review will summarize the biosynthesis of different plant hormones, such as auxin, salicylic acid, gibberellins, cytokinins, ethylene, and abscisic acid, in relation to glucose metabolism.

• Journal of Forest and Environmental Science
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• v.28 no.4
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• pp.232-241
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• 2012

We investigated the relationship between vegetation type and soil carbon dynamics in even-aged alder (Alnus hirsuta) and Korean pine (Pinus koraiensis) plantations in central Korea. Both forests were located on the same soil parent material and occupied similar topographic positions. Soil $CO_2$ efflux in the two plantations was determined using a dynamic chamber method accompanied by measurements of soil moisture content and temperature. Mean soil temperature was similar in the two plantations, but mean soil water content was significantly higher in the alder plantation than in the pine plantation. In both plantations, seasonal patterns in soil $CO_2$ efflux exhibited pronounced variation that corresponded to soil temperature. Soil water content did not affect the seasonal variation in soil $CO_2$ efflux. However, in summer, when soil temperature was above $17^{\circ}C$, soil $CO_2$ efflux increased linearly with soil water content in the alder plantation. Estimated $Q_{10}$ was 3.3 for the alder plantation and 2.7 for the pine plantation. Mean soil respiration during the measurement period in the alder plantation was 0.43 g $CO_2\;m^{-2}\;h^{-1}$, which was 1.3 times higher than in the pine plantation (0.33 g $CO_2\;m^{-2}\;h^{-1}$). Higher soil $CO_2$ efflux in the alder plantation might be related to nitrogen availability, particularly the concentration of $NO_3{^-}$, which was measured using the ion-exchange resin bag method.

• Korean Journal of Soil Science and Fertilizer
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• v.6 no.4
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• pp.239-244
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• 1973

Effects of nitrogen sources on free amino acids, and on photosynthsis-respiration equilibrium point of various positional leaf in soybean were investigated in relation to phosphorus sensitivity. The content of free amino acids was highest in ammonium and lowest in urea treated leaves. Glycine, serine, alanine and especially histidine were high in the ammonium treated leaves. Aspartic acid was high in the nitrate treated leaves. Photosynthesis respiration equilibrium point was higher in the sensitive cultivars, and higher with ammonium than with nitrate. The excess ammonium in plant appears to draw out an intermediate metabolite from carbon fixation pathway resulting in photosynthetic inhibition and activate pentoses phosphate pathway and photorespiration. Such phenomena were likely accentuated in phosphorus sensitive variety.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.9 no.1
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• pp.33-54
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• 2003

The aim of this study was to develop a model that could be used in the design of modified atmosphere packaging (MAP) for peaches. Respiratory data at 5, 10, $20^{\circ}C$ for peaches were gathered and altered for create useful respiration model. Packaging materials were conventional low density polyethylene and polypropylene with anti-fog, and anti-fungi treatments, and thickness was $30{\mu}m$ and $50{\mu}m$ each. Permeability tests were performed to find their oxygen, carbon dioxide, water vapor transmission rate as increases in temperature. Test results were then converted to logarithm format for MAP modeling. The maximum rate of oxygen uptake increased with increasing temperature. Optimum gas composition in the package system for fruits were set according to literature and upper or lower limits of oxygen and dioxide established. To predict gas composition at certain storage time, weight of fruits, film thickness, film type, and other variables, respiration rate was studied at various storage conditions. The results of tests were used to calculate Cameron's model and converted to a cubic estimation equation. The validity of the model was tested experimentally by observing actual atmospheric changes inside packages. This result of study may be useful for designing dynamic gas exchange MAP systems for similar agricultural products.

• Korean Journal of Environment and Ecology
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• v.32 no.6
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• pp.676-685
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• 2018

This study is to compare carbon budget between serpentine sites and non-serpentine sites dominated by Pinus densiflora forest in the Andong serpentine area where has high values of magnesium and low values of calcium, and are usually deficient in nitrogen and phosphorus, but rich in heavy metals such as nickel, chrome, cobalt, etc. and to measure soil $CO_2$ efflux and environmental factors between January 2017 and December 2017. Soil $CO_2$ efflux was measured with LI-6400 once a month; the soil temperature at 10 cm depth, air temperature, soil moisture contents, and solar radiation were measured in continuum. Soil $CO_2$ efflux in the serpentine area and non-serpentine were $151.71{\pm}75.09g\;CO_2{\cdot}m^{-2}month^{-1}$(42.48 ~ 262.61 g $CO_2{\cdot}m^{-2}month^{-1}$) and $165.09{\pm}118.96g\;CO_2{\cdot}m^{-2}month^{-1}$(20.94 ~ 449.24 g $CO_2{\cdot}m^{-2}month^{-1}$), respectively. Carbon storage in the serpentine area and non-serpentine area were 91.90, $222.85ton{\cdot}ha^{-1}$, respectively. Carbon absorption in the serpentine area and non-serpentine area were 7.99, $17.41ton{\cdot}ha^{-1}yr^{-1}$, respectively. Carbon budget in the serpentine area and non-serpentine area were absorbs 5.3, $14.49ton{\cdot}Cha^{-1}yr^{-1}$, respectively.

• Spatial Information Research
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• v.21 no.5
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• pp.15-22
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• 2013

The purpose of this work is to investigate correlation between $CO_2$ concentration and NDVI (Normalized Difference Vegetation Index) in North East Asia. Geographically weighted regression techniques were used to evaluate the spatial relationships between GOSAT (Greenhouse Observing SATellite) $CO_2$ measurement and MODIS (Moderate Resolution Imaging Spectroradiometer) vegetation index. The results reveals that $CO_2$ concentration to be negatively associated with NDVI. The analysis of Global Morans' I index and Anselin Local Morasn's I showed spatial autocorrelation between the overall spatial pattern of $CO_2$ and NDVI. Ultimately, there were clustered patterns in both data sets. The results show that carbon dioxide concentration shows non-random distribution patterns in relation to NDVI clusters, which proves that intense development activities such as deforestation are influencing carbon dioxide emission across the area of analysis. However, as the concentration of carbon dioxide varies depending on a variety of factors such as artificial sources, plant respiration, and the absorption and discharge of the ocean, follow-up studies are required to evaluate the correlations among more related variables.

• Journal of Microbiology
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• v.41 no.1
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• pp.34-40
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• 2003

Aspergillus nidulans, a homothalic ascomycete, has a complete sexual reproductive cycle as well as an asexual one. Both sexual and asexual development are known to be genetically programmed, but are also strongly affected by environmental factors including nutrients, light, temperature and osmolarity. We have examined these factors to define favored conditions for fruiting body (cleistothecium) formation. In general, fruiting body formation was enhanced where carbon and nitrogen sources were sufficient. Limitation of C-source caused predominant asexual development while inhibiting sexual development. When higher concentrations of glucose were supplied, more cleistothecia were formed. Other carbon sources including lactose, galactose and glycerol made the fungus develop cleistothecia very well, whereas acetate caused asexual sporulation only. Organic nitrogen sources like casein hydrolysate and glycine, and an increase in nitrate or ammonium concentration also enhanced sexual development. In addition to nutrient effects, low levels of aerobic respiration, caused either by platesealing or treatment with various chemicals, favored sexual development. Carbon limitation, light exposure and a high concentration of salts promoted asexual development preferentially, suggesting that stress conditions may drive the cell to develop asexual sporulation while comfortable and wellnourished growth conditions favored sexual development.