• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.4
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• pp.71-81
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• 2019

This research was conducted to improve availability of agricultural by-products, national natural resources that could be used as fertilizer source, by estimating the amount of production and collecting main contents of fertilizer substances from previous studies and data, in order to be used as basic data to investigate national resources that could be used as alternatives for imported oil-cakes in the future. Conversion factor was used to estimate annual production of agricultural by-products for main 34 crop types in 2018. For total agricultural by-products, rice straws accounted at 50.3% for the highest proportion, followed by 8.7% of rice husks, showing that by-products from rice harvest accounted at 59.0% for all by-products. Further, there were listed the contents of fertilizer substances (nitrogen, phosphoric acid, potash) in 40 types of by-products from agricultural areas. The average contents of nitrogen, phosphoric acid, and potash in agricultural by-products were 1.43%, 0.59%, and 1.90%, respectively. As a result of estimating the annual nitrogen supply amount from 26 agricultural by-products in 2018, it was found that it could supply 44,911 tons of nitrogen. The investigated by-products contained fertilizer substances such as nitrogen, phosphoric acid, and potash, but the contents were lower compared to castor oil-cake used as main component of organic fertilizer. Therefore, resource management plan needs to be established for efficient use of by-products because time, location, and nutrient content of agricultural by-product production were extremely different. Research on fertilizer and manure using agricultural by-products need to be conducted to develop and distribute alternatives for imported oil-cakes.

• Journal of the Korea Organic Resources Recycling Association
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• v.22 no.3
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• pp.33-40
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• 2014

This study were conducted to evaluate the N mineralization and nitrification rates and to estimate the losses of total carbon and nitrogen by runoff water in soils cooperated with organic composts and bio-char during corn cultivation. For the experiment, the soil texture used in this study was clay loam, and application rates of chemical fertilizer and bio-char were $230-107-190kg\;ha^{-1}$($N-P_2O_5-K_2O$) as recommended amount after soil test and 0.2% to soil weight. The soil samples were periodically taken at every 15 day intervals during the experimental periods. The treatments were consisted of cow compost, pig compost, swine digestate from aerobic digestion system, and their bio-char cooperation. For N mineralization and nitrification rates, it was shown that there were generally low in the soil cooperated with bio-char as compared to the only application plots of different organic composts except for 47 days after sowing. Also, they were observed to be highest in the application plot of swine digestate from aerobic digestion system. For loss of total carbon by run-off water, it was ranged from 1.5 to $3.0kg\;ha^{-1}$ in the different organic compost treatment plots. However, Loss of total carbon with bio-char could be reduced at $0.4kg\;ha^{-1}$ in PC treatment plot. Also, with application of bio-char, total nitrogen was estimated to be reduced at 4.2 (15.1%) and $3.8(11.8%)kg\;ha^{-1}$ in application plots of pig compost and swine aerobic digestate, respectively.

• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.1
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• pp.13-24
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• 2013

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.5
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• pp.72-78
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• 2000

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.6
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• pp.351-356
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• 2006

A long-term experiment was initiated in 1979 at Experiment Farm of Honam Agricultural Research Institute, to investigate the effects of continued use of organic matter (rice straw and compost) along with different levels of nitrogen fertilizer in rice cultivation. The soils of experimental plots is classified as Jeonbug series developed on Fluvio-marine deposits. The application rates of rice straw and compost were 5 Mg/ha/year and 10 Mg/ha/per year, respectively. The fertilizer N application rates per season were 0, 100, 150, 200, and 250 kg/ha. In 2002, after 24 years of experiment, the effect of different treatments on soil pH, characteristics soil organic matter, soil N and P were investigated. The results of the study is summarized as following. The continue use of organic matter tended to lower the soil pH, to increase organic matter and available phosphate contents. The rice straw tended to lower soil pH more than compost, while the effect of compost was greater in increasing soil organic matter and available soil P then rice straw. The application of organic matter resulted in the increase in total organic N in the soil. Such effect was greater in compost application than in rice straw application. In organic N, greatest was amino acid-N, followed by unidentifiable organic N. The least was amino sugar-N. The application of organic matter with and without nitrogen fertilizer affected the in organic fractions of P, particularly Fe-P and Al-P. The application of rice straw tended to increase Ca-P.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.57-64
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• 1997

The research was investigated to determine the effect of organic acids or packaging methods (PA) either alone or in combination on the quality of Aster scaber during storages. The Aster scaber was treated with organic acids and PA, and stored at different temperature $(1\;and\;5^{\circ}C)$. Total plate counts, weight loss, color change, and sensory evaluation were evaluated. Both organic acid treatments, PA, and combined treatment had little effect on the inhibition of total plate counts compared to the control (non-treatment). Organic acid treatments showed less weight reduction compared to the control and nitrogen treated package had the least weight reduction, but the combined treatments showed less weight reduction than organic acid treatments or packaging method alone. Organic acid treatments were little different from the control on color change, but nitrogen packages had the least color change, whereas combined treatments were a little reduced, but little different compared to the control or nitrogen packages. The nitrogen packages showed better effects on the sensory evaluation compared to other treatments and the results of sensory evaluation were consistent with that of weight reduction and color change, but not in total counts. All these results showed better effects in $5^{\circ}C$ rather than $1^{\circ}C$.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.2
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• pp.116-123
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• 2004

This study was conducted to investigate the changes in physicochemical and microbiological properties during fermenting process of organic fertilizer which was made from the mixture of organic materials such as sesame oil cake, fish meal, blood meal, rice bran, ground bone meal, and natural minerals such as illite, crusted oyster shell and loess. They were mixed and fermented for 70 days. The sesame oil cake and rice bran, major ingredients for organic fertilizers, consisted of 7.6 and 2.6% total nitrogen, 3.6 and 4.6% $P_2O_5$, 1.4 and 2.2% $K_2O$, respectively. The ground bone meal included 29.2% $P_2O_5$ and illite included 3.8% $K_2O$. Temperature of organic fertilizer during the fermentation rapidly increased over $50^{\circ}C$ within 2 days after mixing and stabilized similar to outdoor temperature after 40 days. Moisture content decreased from 36.3 to 16.0% after 1 month. C/N ratio of organic fertilizer slightly increased until 30 days and thereafter, it slowly decreased, It resulted from the faster decrease of total nitrogen concentration compared with organic matter. Concentration of $NH_4-N$ in organic fertilizer rapidly increased from 1,504 to $5,530mg\;kg^{-1}$, the highest concentration after 10 days. Meantime, $NO_3-N$ concentration was low and constant about $150mg\;kg^{-1}$ over the whole fermenting period. This result seemed to be due to the high pH. The organic ferfilizer fermented for 70 days was composed of 2.7% N, 2.8% $P_2O_5$, 1.8% $K_2O$, and 35.9% organic matter. Total populations of aerobic bacteria, Bacillus sp. and actinomycetes, after fermenting process, were $12.5{\times}10^{10}$, $45.5{\times}10^{5}$ and $13.6{\times}10^{5}cfu\;g^{-1}$ respectively. Pseudomonas sp. was $71.9{\times}10^{7}cfu\;g^{-1}$ at first, but it rapidly decreased according to the rise of temperature. Yeasts played an important role in the early stage of fermentation and molds did in the late stage.

• Korean Journal of Organic Agriculture
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• v.9 no.1
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• pp.91-108
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• 2001

농업영농활동으로 인한 지하수와 지표수오염이 증가함에 따라 유럽연합(EU)과 각국 정부는 상수원보호를 위한 규제를 마련해 나가고 있다. 농민들의 영농활동을 제한하는 이러한 각종 규제에도 불구하고, 농지로부터 유입되는 상수원의 질산염 함량과 농약농도는 계속적으로 증가하고 있다. 지하수 용탈(질산염)과 지표수 유거(인산염, 농약)는 상수원오염은 주범으로 인식되고 있으며, 어느 지역 상수원의 질산염 오염 위험성은 1) 년간 양분균형 계산, 2) 규칙적 토양질산염 분석 등에 의해 파악이 가능하다. 질산염 용탈 이전에 토양질산염 분석을 통한 토양진단은 질산염 용탈 위험성과 작부체계의 지속성에 대한 필수적인 정보들을 제공하게 된다. 유기질비료를 다량 투입하는 유기농업의 지속성은 1) 양분균형의 과다 계산(질소, 인산, 칼리), 2) 토양질산염진단법, 3) 경운층의 토양인산진단법 등에 평가될 수 있다. 상수원을 가장 효과적으로 보호하기 위해서는 토양진단 최적시비전략과 작부체계가 함에 개발되어져야 한다.

• Journal of Korean Society of Forest Science
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• v.82 no.3
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• pp.246-253
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• 1993

The composition of the nitrogen forms of the organic layer and mineral soil horizons of 8 differing soil type was measured to find a clue to elucidate the problem on the fertility and nitrogen availabilities of forest soils. The ratio of inorganic $N(NH_4-N+NO_3-N)$ to total N was very low in every 0 layer and its maximum was only about 2%. And the inorganic N concentration of every mineral soil horizon was low, and the maximum of its rate to N was 3.7% in surface horizon and about 4.1% in lower horizon. Organic N form of O layer were characterized by the decrease of aminoacid-N, and the increased of hexosamine-N and amide-N according to the advance of decomposing process. The ranges of hydrolyzable-N of every flesh litter, F and H layer of the selected soils were about 80-90% and they- were hardly affected by the differences of tree species and decomposing process. The organic N form of every litter was similar and it was follows : aminoacid-N was not abundant and it ranges were about 40-50%, more than half of hydrolyzable-N. The hexosamine-N was eery poor and it ranged to only 2-7%. The amide-N teas low and about 10-23%. No distinguished difference was seen between the organic N forms of the O layer and surface horizon of dry and wet soils in brown forest soils.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.2
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• pp.204-210
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• 1989

Normally cultured, harvested and yellowed leaves of aromatic tobacco variety. KA 101 were sun-cured under conventional polyethylene film house, air-cured in burley curing barn, and bulk-cured at three temperatures of 40$^{\circ}C$, 50$^{\circ}C$ and 60$^{\circ}C$. respectively, to investigate the effects of curing conditions on quality and chemical properties of leaf tobacco. Air-cured leaves had the poorest quality by price with little difference between that of sun-cured and three bulk-cured ones. Air-cured leaves were higher in ammonia nitrogen, protein nitrogen, total nitrogen, ash content and pH, but lower in sugar content when it compared with those of sun-cured and three bulk-cured ones. The curing variables tested did not affect the content of pet. ether ext. and volatile organic acids. The content of pet. ether ext., volatile organic acids, and most of volatile neutrals tended to decrease or not to change as the bulk-curing temperature increased. A quality index, (volatile organic acids, mg/l00g+％ pet. ether ext.) / ％(ash+pH) x 10, was found to be most accurate and easy to apply for the quality evaluation of aromatic tobaccos.