• Journal of Environmental Impact Assessment
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• v.26 no.2
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• pp.127-139
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• 2017

Measurements of net ecosystem exchange (NEE) of $CO_2$ based on the eddy covariance technique provide reasonable carbon balance estimates in response to local environmental conditions. In South Korea, the forest ecosystems cover approximately 64% of the total area, thereby strongly affecting regional carbon balances. Cultivated croplands that cover about 17% of the total area should also be considered when calculating the carbon balance of the country. In this study, our objectives were (a) to quantify the range and seasonal variation of NEE at forest ecosystems, including deciduous, coniferous, and mixed forests, and agricultural ecosystems, including rice paddies and a potato field, in South Korea and (b) to compare NEE at ten Fluxnet sites that have the same or similar ecosystems as found in South Korea. The results showed that the forest and agricultural ecosystems were carbon sinks. In Korea, NEE at the forest ecosystems varied between -31 and $-362gC/m^2/yr$, and NEE at the croplands ranged from -210 to $-248gC/m^2/growing$ season. At the deciduous forest, NEE reached low values in late spring, early summer, and early autumn, while at the coniferous forest, it reached low values in spring, early summer, and mid autumn. The young mixed forest was a much stronger carbon sink than the old-growth deciduous and coniferous forests. During each crop growing season, beet had the lowest NEE value within six crops, followed by wither wheat, maize, rice, potato, and soybean. These results will be useful for designing and applying management strategies for the reduction of $CO_2$ emissions.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.3
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• pp.300-306
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• 2000

This experiment was carried out to determine the contributions of acetate, glucose, amino acids and amino acid metabolites as carbon precursors for the incorporation of radioisotope, in intramuscular and subcutaneous adipose tissue and the effects of insulin on lipogenesis and adrenergic agent, norepinephrine on lipolysis in both tissues. The rate of incorporation of $C^{14}$ labelled acetate, glucose, leucine, isoleucine and ${\alpha}$-ketoisocaproic acid into adipose tissue has been measured in subcutaneous and intramuscular adipose tissues. The rate of incorporation was greater (p<0.05) from acetate than glucose in both subcutaneous and intramuscular adipose tissue and the rate of incorporation of carbon precursors into adipose tissues was greater in subcutaneous than in intramuscular adipose tissues. In comparison of amino acids, the rate was highest (p<0.05) with leucine followed by isoleucine and ${\alpha}$-ketoisocaproic acid in subcutaneous adipose tissue, in which there were no differences. Also, in intramuscular tissue, leucine was highest (p<0.05), and the rate of incorporation decreased in the same order. The rates of carbon precursor incorporation appeared to be higher in subcutaneous than in intramuscular tissue. For incorporation of radio-labelled acetate and glucose into intramuscular adipose tissue. preincubated for 48 hrs with insulin and IGF-1, insulin was the most effective to stimulate the incorporation of precursors in both substrates but there was no difference between insulin and IGF-1 in glucose incorporation. For glyceride-fatty acid synthesis, acetate was significantly (p<0.05) greater than glucose in both subcutaneous and intramuscular adipose tissue, and glyceride-glycerol synthesis was greater (p<0.05) for glucose than acetate in both adipose tissues. The rates of lipogenesis from both precursors were slightly greater in subcutaneous than intramuscular adipose tissue. There was significant (p<0.05) site effect in insulin treatment for glyceride-fatty acid synthesis. But there were no significance in control and norepinephrine. For glyceride-glycerol synthesis, there was no site effect caused by hormonal treatment. Insulin was the most effective (p<0.05) in glyceride fatty acid synthesis, while norepinephrine was the same as control. Compared with control, glyceride-glycerol synthesis from acetate in insulin treatment was significantly (p<0.05) low in subcutaneous, but high in intramuscular tissue. At the same time, in both tissues, it was lower in norepinephrine treatment than in control. Glyceride-glycerol synthesis from glucose was highest (p<0.05) in norepinephrine treatment followed by insulin although there was no significance between insulin and control. Lipolysis was not affected by insulin but was increased by norepinephrine when added to adipose tissue incubations in vitro. Rates of basal lipolysis were greater in subcutaneous adipose tissue than in intramuscular adipose tissue.

• Journal of the Korean Wood Science and Technology
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• v.48 no.5
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• pp.732-744
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• 2020

In this study, a torrefaction of Quercus serrata to manufacture a molded charcoal was performed, investigated material properties, fuel characteristics, and performed a quantitative analysis of hazardous gases which occur during a combustion process. In addition, a molded charcoal in market was selected as a control group, and a comparative analysis was performed. As a result, the higher heating value (HHV) of the torrefied specimen was about 14% higher than that of molded charcoal, and its ash content was about 51 times lower. Moreover, after performing a quantitative assessment of hazardous gases (carbon monoxide, nitrogen oxide, and sulfur dioxide) which were produced when each specimen was combusted for 900 seconds in an enclosed chamber, it was confirmed that the maximum value of generated amount of carbon monoxide on the torrefied specimen was about 50 times lower than that of the existing molded charcoal. Therefore, it was shown that the torrefied specimen produced in this study had a higher heating value than the molded charcoal in the market, and a very low amount of carbon monoxide generated during the combustion process.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1615-1615
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• 2001

During the past ten years, Near Infrared Spectroscopy has been successfully applied to the analysis of a great variety of agriculture products. Previous works (Morra et al., 1991; Salgo et al., 1998) have shown the potential of this technology for soil analysis, estimating different parameters just with one single scan. The main advantages of NIR applications in soils are the speed of response, allowing the increase of the number of samples analysed to define a particular soil, and the instantaneous elaboration of recommendations for fertilization and soil amendment. Another advantage is to avoid the use of chemical reagents at all, being an environmentally safe technique. In this paper, we have studied a set of 129 soil samples selected from representative glasshouse soils from Southern Spain. The samples were dried, milled, and sieved to pass a 2 mm sieve and then analysed for organic carbon, total nitrogen, inorganic nitrogen (nitrate ammonium), hygroscopic humidity, pH and electrical conductivity in the 1:1 extract. NIR spectra of all samples were obtained in reflectance mode using a Foss NIR Systems 6500 spectrophotometer equipped with a spinning module. Calibration equations were developed for seven analytical parameters (ph, Total nitrogen, organic nitrogen, organic carbon, C/N ratio and Electric Conductivity). Preliminary results show good correlation coefficients and standard errors of cross validation in equations obtained for Organic Carbon, Organic Nitrogen, Total Nitrogen and C/N ratio. Calibrations for nitrates and nitrites, ammonia and electric conductivity were not acceptable. Calibration obtained for pH had an acceptable SECV, but the determination coefficient was found very poor probably due to the reduced range in reference values. Since the estimation of Organic Carbon and C/N ratio are acceptable NIIRS could be used as a fast method to assess the necessity of organic amendments in soils from Mediterranean regions where the low level of organic matter in soils constitutes an important agronomic problem. Furthermore, the possibility of a single and fast estimation of Total Nitrogen (tedious determination by modifications of the Kjeldahl procedure) could provide and interesting data to use in the estimation of nitrogen fertilizer rates by means of nitrogen balances.

• Journal of the Korean Wood Science and Technology
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• v.27 no.2
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• pp.70-77
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• 1999

Objective of this research is to obtain fundamental data of carbonized wood wastes for soil condition, de-ordorization, absorption of water, carrier for microbial activity, and purifying agent for water quality of river. The carbonization technique and the properties of carbonized wood wastes(thinned trees) are analyzed. Proximate analysis shows the thinned wood contains 0.22-0.73% ash, 77-80% volatile matter, and 10-14% fixed carbon. The charcoal yield decreases and the shrinkage rate increases as the carbonization temperature and time increase. The charcoal yields of Larix leptolepis, Pinus rigida and Pinus densiflora are high, whereas those of Pinus koraiensis and Quercus variabilis are low. The shrinkage rate by carbonization has same trend as water removal of wood. The specific gravity after the carbonization decreases about 50% comparing to green wood. The charcoal has 0.89-4.08% ash, 6.31-13.79% volatile matter, and 73.9-83.5% fixed carbon. As the carbonization temperature and time increase, pH of charcoal increases. When the carbonization temperature is $400^{\circ}C$, pH is about 7.5. When the temperature is between 600 to $800^{\circ}C$, pH is about 10 with small difference. The water-retention capacity is not affected by the carbonization temperature and time. The water-retention capacity within 24hr is about 2.5 - 3times of sample weight, and the equivalent moisture content becomes 2-10% after 24 hr.

• The Korean Journal of Pesticide Science
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• v.14 no.2
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• pp.148-156
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• 2010

S59-4 isolate was evaluated as a potential biocontrol agent using in vivo wounded garlic bulb assay. When the spore suspension ($10^5$ spores/$m\ell$) of Penicillium hirsutum was co-inoculated with cell suspension of S59-4 isolate on wounded garlics, the isolate showed high suppressive effect to disease development. The isolate was identified as Pantoea agglomerans S59-4(Pa59-4) through Biolog system. Furthermore, soaking garlic bulbs in the suspension of Pa59-4 significantly reduced garlic decay caused by P. hirsutum. The optimal concentration of Pa59-4 for controlling garlic blue mold was $10^7\sim10^8$ cfu/$m\ell$. And suppressive effect of Pa59-4 on garlic storage decay reduced as inoculation concentration of Penicillium hirsutum increased. In addition in order to investigate population dynamics of Pa59-4 on application site of garlic cloves, two antibiotic markers, pimaricin and vancomycin were selected. Bacterial density of Pa59-4 on the wounded garlic cloves increased continuously both under room temperature condition and low temperature condition until 30days after application of Pa59-4, meanwhile that of Pa59-4 on intact garlic cloves increased until 15days after application of Pa59-4 and thereafter decreased continuously. Two culture media for mass-production of Pa59-4, LB medium and TSB medium, were selected. By-product of bio-fungicide formulated by mixing white carbon and bacterial suspension of Pa59-4 suppressed by 40 to 50% garlic blue mold. Above results suggest that Pa59-4 be a promising control agent against garlic blue mold.

• Korean Journal of Environmental Agriculture
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• v.15 no.3
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• pp.362-371
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• 1996

This study was conducted to investigate the biochemical properties of isolated bacteria, low temperature tolerant methanogens which were selected for use as inoculum for anaerobic fermentation of agricultural and livestock wasted at low temperature. The results, obtained were summarized as follows: Low temperature tolerant methanogens were isolated from the samples which showed the high methanogenesis rate by enrichment culture at low temperature in methanol medium. These methanogens, Methanobacterium M-251 and Methanobacterium M-253 were isolated from swampy sediment at latitude $56.9^{\circ}$, Methanosarcina mazei M-372 from lake sediment IV at latitude $55.0^{\circ}$ N, and Methanobacterium formicicum M-375 from tidal land soil at latitude $37.0^{\circ}N$, respectively. The isolated anaerobic bacteria could not use sugars as carbon sources. The optimum pH value for the growth of M-251 and M-375 was 6.8, but those for M-253 and M-372 6.5 and 7.0, respectively. The minimum growth temperature of isolated, M-251 and M-253 were $8^{\circ}C$ and the optimum temperature $30^{\circ}C$, while the minimum of M-392 and M-395 were $13^{\circ}C$ and the optimum $37^{\circ}C$. The growth rate of isolates at $17.5^{\circ}C$ were lower by 32-50% than that of $30^{\circ}C$. The isolated Methanobacterium strains such as M-251, M-253, and M-375 have lower cell yield, 0.38-1.21g/1M $CH_4$ than 1.14-1.51g/1M $CH_4$ of Methanosarcina mazei M-372.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.193-193
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• 2017

The black heart in potato is a physiological disorder that occurs when potatoes suffer from breathing problems. When storing potatoes at a low temperature around $0^{\circ}C$, there is a high possibility that the respiration rate of potato will rise and black heart will occur. Also, respiration can occur easily and briefly in a state where high temperature and ventilation is insufficient. Recently, as black heart has been occurred continuously and severely in South Korea, here we tried to identify the causes of black heart in potato and to develop the control strategy of this disorder. Firstly, we analyzed the influence on the black heart on the basis of preservation containers (breathable plastic box, burlap bag, paper box, sealed plastic box). After harvesting the potato which is cv. Superior, it preserved for 6 months under conditions of temperature $3.5^{\circ}C{\pm}0.2$ and humidity 85%, after then we surveyed the incidence of emergence rate, rate of weight loss and occurrence rate of black heart. Secondly, in order to investigate the time point of black heart initiation under the oxygen concentration condition of 1% or less, The potatoes were used for this experiment stored for 6 months in a aerated plastic box under conditions of temperature $3.5^{\circ}C{\pm}0.2$ and humidity 85% under sufficient oxygen condition. After stored for 6 month, those were stored at $15^{\circ}C$ and below 1% of oxygen for 25 days, and then the incidence of black heart was surveyed. Thirdly, to investigate the effects of the number of days after harvest on the occurrence of black heart, it was examined the occurrence of black heart stored on 40 days and 100 days after harvesting under sealed condition and vacuum condition. The temperature condition of potato storage was stored was at $4^{\circ}C$ and $25^{\circ}C$ in humidity 85%. As a result of investigating the occurrence of black heart depending on the storage containers, all of the potatoes stored in the sealed plastic box had been occurred black heart. However, black heart of the potatoes in the other treatments did not. Potato preserved under the condition of below 1% of oxygen was found to occur 32% black heart after 25 days of storage. The potatoes corresponding to the required number of days after harvesting were stored for 31 days and the black heart was examined on the occurred. As a result, the potatoes which were 40 days after the harvest did not have black heart under sealed condition and vacuum condition. But potatoes harvested 100 days after harvesting had a black heart incidence of 95.7% under sealed condition at $4^{\circ}C$. The potato placed in the vacuum condition and a sealed state at $25^{\circ}C$ was transformed into anaerobic respiration, the inner tissue of tuber collapsed. Therefore, it is considered that black heart is caused by the breathing trouble in the central part when the oxygen is almost consumed after the aerobic respiration which gradually consumes the oxygen. We conclude that the black heart occurred in the central part where exchange of oxygen and carbon dioxide is the slowest is sensitive to respiration disorder. It is thought that research to investigate black heart generation time according to storage conditions and post-harvest state of potatoes is further necessary.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.61-62
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• 2003

Clonal propagation of high-value forest trees through somatic embryogenesis (SE) has the potential to rapidly capture the benefits of breeding or genetic engineering programs and to improve raw material uniformity and quality. A major barrier to the commercialization of this technology is the low quality of the resulting embryos. Several factors limit commercialization of SE for Corsican pine, including low initiation rates, low culture survival, culture decline causing low or no embryo production, and inability of somatic embryos to fully mature, resulting in low germination and reduced vigour of somatic seedlings. The objective was to develop a Corsican pine maturation medium that would produce cotyledonary embryos capable of germination. Treatments were arranged in a completely randomized design. Data were analyzed by analysis of variance, and significant differences between treatments determined by multiple range test at P=0.05. Corsican pine (Pinus nigra var. maritima) cultures were initiated on modified !P6 medium. Modifications of the same media were used for culture multiplication and maintenance. Embryogenic cultures were maintained on the same medium semi solidified with 2.5 g/l Gelrite. A maturation medium, capable of promoting the development of Corsican pine somatic embryos that can germinate, is a combination of iP6 modified salts, 2% maltose, 13% polyethylene glycol (PEG), 5 mg!l abscisic acid (ABA), and 2.5 g/l Gelrite. After initiation and once enough tissue developed they were grown in liquid medium. Embryogenic cell suspensions were established by adding 0.951.05 g of 10- to 14-day-old semisolid-grown embryogenic tissue to 9 ml of liquid maintenance media in a 250ml Erlenmeyer flask. Cultures were then incubated in the dark at 2022$^{\circ}$C and rotated at 120 rpm. After 2.53 months on maturation medium, somatic embryos were selected that exhibited normal embryo shape. Ten embryos were placed horizontally on 20 ml of either germination medium ($\frac{2}{1}$strength Murashige and Skoog (1962) salts with 2.5 g/l activated charcoal) or same medium with copper sulphate adjusted to 0.25 mg/1 to compensate for copper adsorption by activated carbon. 2% and 4% maltose was substituted by 7.5% and 13% PEG respectively to improve the yield of the embryos. Substitution of' maltose with PEG was clearly beneficial to embryo development. When 2% of the maltose was replaced with 7.5% PEG, many embryos developed to large bullet-shaped embryos. At latter stages of development most embryos callused and stopped development. A few short, barrel-shaped cotyledonary embryos formed that were covered by callus on the sides and base. When 4% of the maltose was removed and substituted with 13% PEG, the embryos developed further, emerging from the callus and increasing yield slightly. Microscopic examination of the cultures showed differing morphologies, varying from mostly single cells or clumps to well-formed somatic embryos that resembled early zygotic embryos only liquid cultures with organized early-stag. A procedure for converting and acclimating germinants to growth in soil and greenhouse conditions is also tested. Seedling conversion and growth were highly related to the quality of the germinant at the time of planting. Germinants with larger shoots, longer, straighter hypocotyls and longer roots performed best. When mature zygotic embryos germinate the root emerges, before or coincident with the shoot. In contrast, somatic embryos germinate in reverse sequence, with the cotyledons greening first, then shoot emergence and then, much later, if at all, the appearance of the root. Somatic seedlings, produced from the maturation medium, showed 100% survival when planted in a field setting. Somatic seedlings showed normal yearly growth relative to standard seedlings from natural seed.

• Journal of Bio-Environment Control
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• v.31 no.3
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• pp.221-229
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• 2022

This study was aimed to investigate spatial and vertical characteristics of greenhouse environments according to the location of the environmental sensors, and to investigate the correlations between temperature, light intensity, and carbon dioxide (CO₂) concentration according to the type of greenhouse. Temperature, relative humidity (RH), CO₂, and light sensors were installed in the four-different vertical positions of the whole canopy as well as ground and roof space at the five spatial locations of the Venlo greenhouse. Also, correlations between temperature, light intensity, and CO₂ concentration in Venlo and semi-closed greenhouses were analyzed using the Curve Expert Professional program. The deviations among the spatial locations were larger in the CO₂ concentration than other environmental factors in the Venlo greenhouse. The average CO₂ concentration ranged from 465 to 761 µmol·mol^-1 with the highest value (646 µmol·mol^-1) at the Middle End (4ME) close to the main pipe (50Ø) of the liquefied CO₂ gas supply and lowest (436 µmol·mol^-1) at the Left Middle (5LM). The deviation among the vertical positions was greater in temperature and relative humidity than other environments. The time zone with the largest deviation in average temperature was 2 p.m. with the highest temperature (26.51℃) at the Upper Air (UA) and the lowest temperature (25.62℃) at the Lower Canopy (LC). The time zone with the largest deviation in average RH was 1 p.m. with the highest RH (76.90%) at the LC and the lowest RH (71.74%) at the UA. The highest average CO₂ concentration at each hour was Roof Air (RF) and Ground (GD). The coefficient of correlations between temperature, light intensity, and CO₂ concentration were 0.07 for semi-closed greenhouse and 0.66 for Venlo greenhouse. All the results indicate that while the CO₂ concentration in the greenhouse needs to be analyzed in the spatial locations, temperature and humidity needs to be analyzed in the vertical positions of canopy. The target CO₂ fertilization concentration for the semi-closed greenhouse with low ventilation rate should be different from that of general greenhouses.