• Proceedings of the Korean Society of Crop Science Conference
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• 한국작물학회 2022년도 추계학술대회
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• pp.168-168
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• 2022

According to the 5th Climate Change Report, global average temperature in 2081~2100 will increase 1.8℃ based on RCP 4.5 and 3.7℃ based on RCP 8.5 from the current climate value (IPCC Working Group I AR5). As temperature is expected to increase due to global warming and the intensity and frequency of rainfall are expected to increase, damage to crops is expected, and countermeasures must be taken. This study intends to evaluate rice growth in terms of nitrogen utilization efficiency according to future climate change conditions. In this experiment, Oryza sativa cv. Shindongjin were planted at the SPAR facility of the NICS in Wanju-gun, Jeollabuk-do on June 10, and were planted and grown according to the standard cultivation method. Cultivation conditions are high temperature, high CO₂ (current temperature+4.7℃·CO₂ 800ppm), high temperature (current temperature+4.7℃·CO₂ 400ppm), current climate (current tempreture·CO₂ 400 ppm). Nitrogen was varied as 0, 9, 18 kg/10a. The N content and C/N ratio of all rice leaves, stems, and seeds increased at high temperature, and the N content and C/N ratio decreased under high temperature and high CO₂ conditions com pared to high temperature. Compared to the current climate, NUE increases by about 8% under high temperature and high CO₂ conditions and by about 2% under high temperature conditions. This seems to be because the increase in temperature and CO₂ induced the increase in biomass. ANUE related to yield decreased by about 70% compared to the current climate under high temperature conditions, and decreased by about 45% at high temperature and high CO₂, showing a tendency to decrease compared to high temperature. This appears to be due to reduced fertility and poor ripening due to high temperature stress. However, as the nitrogen increased, the number of ears and the number of grains increased, slightly offsetting the production reduction factor.

• Korean Journal of Environmental Agriculture
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• 제31권3호
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• pp.212-216
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• 2012

BACKGROUND: Green manure and graminaceousmanure crops have several benefits, such as improving soil physical and chemical properties and utilizing excessive greenhouse nutrients that they have a potential to be a water pollutant source. METHODS AND RESULTS: The objective of this study was to investigate nitrogen (N) supplying capabilities of green manure and graminaceous manure crops for lettuce (Lactuca sativa L.) and Chinese cabbage (Brassica campestris L.) grown under greenhouse conditions. For this two leguminous manures (Crotalaria juncea (Cr.) and Sesbaniaexaltata (Se.)) and two graminaceous manures (Sorghum bicolor; Haussolgo(Ha.) and Sudangrass (Sg.)) in the greenhouse were grown, cut, and incorporated into the greenhouse soil before planting. Chemical nitrogen (N) fertilizer rate was estimated based on N recommendation for lettuce and Chinese cabbage. 100% of the N recommended rates (1N) were 70 kg N $ha^{-1}$ for lettuce and 60 kg N $ha^{-1}$ for Chinese cabbage and 50% of the N recommendation rates (0.5N) were 35 kg N $ha^{-1}$ for lettuce and 30 kg N $ha^{-1}$ for Chinese cabbage. Nitrogen treatments were control (0N), Cr., Se., Cr + 0.5 N, Se + 0.5 N, Ha + 0.5 N, Sg + 0.5 N, and N recommendation rate (1N). Incorporated N from green manure and graminaceous manure crops were 130, 116, 93, and 87 kg N $ha^{-1}$ for Cr., Se., Ha., and Sg., respectively. Lettuce and Chinese cabbage were grown after incorporated green manure crops into the greenhouse soil. There was no significant difference in lettuce and Chinese cabbage yields under N treatments except control (0 kg/ha). Nitrogen use efficiency (NUE)was from 44% to 73% and the highest NUE was under Se. treatment. Although yields were not statistically different under N treatments except control, actual yield increase ranged from 170 to 1,100 kg/ha for lettuce and ranged from 2,770 to 5,210 kg/ha for Chinese cabbage compared to yield under N recommendation rate. Estimated economic benefit from this would be higher approximately between \2,770,000 and \5,210,000/ha under N treatments except control than the N recommendation rate. CONCLUSION: These results suggest that incorporating green manure crops, such as Cr. and SeSe. into soil or adding 0.5 N after incorporation of them can be beneficial in many ways in that it increases economic return because of yield increase, reduces the use of chemical N, and decreases the negative environmental impact on water quality because excessive N in the greenhouse soil can be used by green manure crops during the fallow.

• Journal of the Korea Organic Resources Recycling Association
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• 제28권4호
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• pp.77-85
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• 2020

This study analyzes the effects of mixed fermented organic fertilizer on chinese cabbage growth and soil properties in order to investigate the nutritional effects of organic fertilizers, which are developed as an alternative fertilizer for imported castor oil cake. In this study, four treatments were set up: 100% and 200% rate of nitrogen application (320 kg ha-1 for Chinese cabbage) on mixed fermented organic fertilizer A(FA) and mixed fermented organic fertilizer B(FB), respectively, 100% rates of the mixed expeller cake (MEC) fertilizer, and the untreated control. Results revealed that the growth and yield of Chinese cabbage increased as more fermented organic fertilizer was used. However, while there were no significant differences in growth characteristics between treatments of 100% rate of mixed fermented organic fertilizer and 100% rate of MEC, the impacts on yields resulted similar. The nitrogen use efficiency (NUE) of Chinese cabbage was measured a range of 20-31% depending on the response to treatment. The 100% FA showed the same as NUE and nitrogen absorption with 100% rate of MEC. Regarding soil properties after cultivation, there were no significant differences among the effects of fertilizers in pH, EC, soil organic matter, and available phosphate. However, the content of exchangeable cations(K, Ca, Mg) was higher in areas treated with mixed fermented organic fertilizer than in untreated areas. Furthermore, the bacterial population density in the soil was higher in areas treated with mixed fermented organic fertilizer than in untreated areas and increased as more mixed fermented organic fertilizer was used. There were no significant differences in the population density of actinomycetes and fungi when fertilizer was applied to the soil. These results also show that FA, as a alternative organic fertilizer for imported castor oil cake, has similar nutritional effects as that of MEC. Therefore, further research the appropriate amounts of fertilizer is required to achieve economical and eco-friendly nutrient management.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제52권3호
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• pp.296-302
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• 2007

This study was conducted to evaluate the effect of slow release fertilizers (SRF), crotonylidene diurea (CDU) and latex coated urea (LCU), on nitrogen (N) use efficiency (NUE) and nitrate-N leaching in a silty clay loam soil under polyethylene film mulching (PFM) for sesame cultivation. In PFM plot, concentrations of $NO_3-N$ and $NH_4-N$ in SRF applied soils were less than that in the urea plot during the whole growing period. However, $NO_3-N$ and $NH_4-N$ in all the non-mulched plots (NM) were not significantly different. Urea-N in soil treated with SRF was higher than urea plot until 50 days after application and was comparable in all the treatments after 50 days. $NO_3-N$ concentrations in leached solution in 21 days after urea fertilization in PFM and NM were 26 mg $L^{-1}$ and 83 mg $L^{-1}$, respectively. However, $NO_3-N$ in leached solution at applied CDU and LCU was less than that of urea similar to nitrate concentration in soil. $NO_3-N$ in leached solution in applied CDU and LCU in 44 days after application was about 25% lower than that urea plot and PFM, while the $NO_3-N$ concentration of CDU and LCU treatment in NM did not changed. Application of SRF increased the yield of sesame and N recovery compared to urea and there was a little difference between SRF and N levels. In conclusion, application of 80% N level with SRF increased N recovery and reduced nitrate leaching without reduction of yields compared with urea application.

• Korean Journal of Agricultural and Forest Meteorology
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• 제25권4호
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• pp.346-358
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• 2023

Due to the acceleration of climate change or global warming, it is important to predict rice productivity in the future and investigate physiological changes in rice plants. The research aimed to explore how rice adapts to climate change by examining the response of nitrogen absorption and nitrogen use efficiency in rice under elevated levels of carbon dioxide and temperature, utilizing the SPAR system for analysis. The temperature increased by +4.7 ℃ in comparison to the period from 2001 to 2010, while the carbon dioxide concentration was held steady at 800 ppm, aligning with South Korea's late 21st-century RCP8.5 scenario. Nitrogen was applied as fertilizer at rates of 0, 9, and 18 kg 10a^-1, respectively. Under conditions of climate change, there was an 81% increase in the number of panicles compared to the present situation. However, grain weight decreased by 38% as a result of reduction in the grain filling rate. BNUE, indicative of the nitrogen use efficiency in plant biomass, exhibited a high value under climate change conditions. However, both NUEg and ANUE, associated with grain production, experienced a notable and significant decrease. In comparison to the current conditions, nitrogen uptake in leaves and stems increased by 100% and 151%, respectively. However, there was a 25% decrease in nitrogen uptake in the panicle. Likewise, the nitrogen content and NDFF (Nitrogen Derived from Fertilizer) in the sink organs, namely leaves and roots, were elevated in comparison to current levels. Therefore, it is imperative to ensure resources by mitigating the decrease in ripening rates under climate change conditions. Moreover, there seems to be a requirement for follow-up research to enhance the flow of photosynthetic products under climate change conditions.

• 한국프랑스학논집
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• 제108권
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• pp.69-113
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• 2019

S'il est évident que la publication de la Deffence marquait le triomphe du français sur le latin dans le domaine littéraire, elle annonçait également une nouvelle idée sur l'imagination à laquelle Du Bellay préfère le mot d'invention(inventio). Aux yeux de Du Bellay, l'art n'est que la part la plus superficielle du travail poétique. L'essentiel de la poésie, sa "sève" ou son "énergie" réside dans son contenu intellectuel. Pour inventer, c'est-à-dire trouver cet energeia des choses, si l'on reprend le terme d'Aristote, et ce qui constitue l'objet de l'imitation et de la représentation, le poète doit faire opérer l'imagination naturelle par laquelle peut se découvrir ce qui est caché dans la nature ou ce que la Nature a caché dans les choses imitées. Cette invention ou cette imagination naturelle exige au poète de se munir non seulement de la finesse et de la sagacité intellectuelles mais de l'art naturel qui se différencie de l'art porté sur "la nue écorce", parce qu'il peut transposer le naturel des choses en langue poétique et fictive. Cela peut témoigner aussi de l'inspiration authentique du poète. Cette idée sur le dynamisme créatif de l'imagination naturelle permet au poète de saisir la force vitale immanente aux choses qu'il imite. Du Bellay refuse ainsi de considérer les forces productrices du texte comme objectives, extérieures au poète. Considérée jusqu'ici comme comme une manifestation de la Pléiade pour la langue française, la Deffence nous propose une des idées primordiales sur l'imagination qui découvre "la vive Energie" qui caractérise le naturel. Cette notion d'imagination naturelle contibue à assurer l'individualité et la créativité aux poètes, puisqu'ils auront la liberté de saisir le naturel invisible en se donnant la propre manière.