• Korean Journal of Soil Science and Fertilizer
• /
• v.33 no.5
• /
• pp.347-355
• /
• 2000

To determine nitrogen balance (Input-Output) of Korea that was asked by Joint Working Party of the Committee for Agriculture and the Environment Policy Committee, OECD, nitrogen input and output were separately investigated as followings: nitrogen input included the amounts of chemical fertilizer consumption, cattle manure production, and biological nitrogen fixation in the national scale, and nitrogen output summed amounts withdrawn by crop and pasture harvesting, and crop residue removal, and lost by denitrification. In 1997, nitrogen balance of Korea was $158kg\;ha^{-1}$ and $211kg\;ha^{-1}$ on including and excluding denitrification loss, respectively. N balance excluded N loss by denitrification and N withdrawal by crop residues on nitrogen output was $250kg\;ha^{-1}$, which OECD asked to except two items from N balance determination because participants were not enough their data. Nitrogen balance was increased to 1.7~2.3 times in 1997 compared with 70 and $162kg\;ha^{-1}$ in 1985, which calculated on the condition of including denitrification and excluding denitrification and removal of crop residues in nitrogen output, respectively. This increase was caused mainly by increasing livestock manure production and chemical fertilizer consumption together with agricultural land area decrease. Nitrogen input was composed with 59% of chemical fertilizer. 42% of cattle manure and 5% of others in 1997, and output was with 73% of crop production, 23% of crop residue withdrawal and 4% of pasture production. Average nitrogen balance excluded N loss by denitrification and N withdrawals by crop residues in 1995~1997 calculated by OECD was $253kg\;ha^{-1}$, which was the second highest rank in OECD participants following $262kg\;ha^{-1}$ of Netherlands. Japanese N balance that has similar farming system with us was $135kg\;ha^{-1}$.

• 비료회보
• /
• s.341
• /
• pp.28-42
• /
• 1987

• Proceedings of the Korean Society of Grassland Science Conference
• /
• 2000.09a
• /
• pp.108.2-109
• /
• 2000

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2001.09a
• /
• pp.152-153
• /
• 2001

• Korean Journal of Soil Science and Fertilizer
• /
• v.19 no.2
• /
• pp.139-145
• /
• 1986

In order to study the influence of nitrate reduction to ionic balance in tissue of tobacco plant, differneces in amounts of those cations and anions were determined and these balances were compared with contents of organic acids and activities of nitrate reductase, while they were fertilized with different nitrogen sources ($NO_3-N$, $NH_4-N$, $NO_3+NH_4-N$) in water culture. The results of studies are summerized as follows; 1. Total uptake of inorganic cations was the highest in nitrate-fed plants, whereas that of inorganic anions showed the highest level in the plants grown with the mixture ($NO_3+NH_4$). The amounts of inorganic cations and anions were comparable in two treatments containing $NH_4-N$, but in plants treated with nitrate only had much higher level of inorganic cations than others. 2. Deficiency in the amount of inorganic anions in nitrate-fed plants was balanced with organic acids, dominantly with malic acid among them. But another two $NH_4-N$ fed plant sustained equilibrium between inorganic cations and anions. 3. Reduction of nitrate was raised in tissues of nitrate-fed plants. By the results of nitrate reduction, cations maintained equilibrium with nitrate ion were let loose. The replacement of inorganic anions with organic anions could be a compensation process for the loss of uptaken nitrate ions which must be reduced to be incorporated into organic N compounds.

• Proceedings of the Korean Society of Organic Agriculture Conference
• /
• 2008.12a
• /
• pp.139-145
• /
• 2008

1) 밭 토양의 질소공급능력은 밭작물 양분요구량의 1.2배였고, 논토양에서는 1.02로, 평균 1.11이었다. 2) 밭 토양에서 Ca, K 함량은 CNCs보다 낮았고, TN, Mg 함량은 CNCs보다 높았다. 논토양에서는 Ca, Mg, K는 CNCs보다 낮아서 양분의 불균형을 이루고 있다. 3) 작물생산량 중의 조사료 생산비율은 68.1%였다. 4) 조농비는 41:59(조사료 자급비율 91.4%) 5) 토양으로의 가축분뇨 질소환원 가능량은 1,034kg(발생 질소량의 60%)로 추정되었다. 6) 토양으로부터 작물로의 질소공급량은 토양 질소량의 72.4%인 1,383.3kg N으로 추정되었고, 천연양분공급량은 298.6 kg N, 잔류양분 287.7 kg N으로 추정되었다. 7) 토양-작물-가축간의 물질수지는 거의 균형을 이루고 있다고 판단되지만, 토양진단을 통한 양분불균형의 개선이 필요하고, 벼 재배 후 월동 사료작물 재배면적의 확대로 조사료 자급 율을 높이므로, 조농비의 개선이 필요 8) 특히 논 토양의 유박비료 시용량을 가축분뇨로 전량 대체하는 것이 경지 내에서의 물질순환 유지에 필요하다고 판단된다.

• Journal of Korean Home Economics Education Association
• /
• v.24 no.2
• /
• pp.51-62
• /
• 2012

This research examined the method and amount changes of recommended protein intakes(RPI) for male and female adult, and pregnant lactating women from 1962's Recommended Dietary Allowances for Korean(KRDA) to 2010's Dietary Reference Intakes for Koreans(KDRIs) revised. As male and female adult's RPI calculation, factorial method was applied until 1989 KRDA, after that nitrogen balance study was applied. Basal factor in factorial method was standard protein(egg or milk protein) requirement or obligatory nitrogen(protein) loss. On the other hand, basal factor in nitrogen balance study was minimum dietary protein requirement to maintain nitrogen equilibrium balance(nitrogen intake = nitrogen excretion). Adjusting factors of RPI were stress and/or protein requirement difference among people. The RPI of male adults were 50~80 g/day, that of female adults were 45~70 g/day. The additional RPI of pregnant women were 10~30 g/day, were calculate based upon the extra protein needs caused by unborn child development. The pregnant women's additional RPI of 2010's KDRIs revised in the periods of first, second, and third trimester were 0, 15, 30 g/day, respectively. The additional RPI of lactation women were 20~30 g/day, were calculated based upon the extra protein needs caused by maternal milk secretion.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.22 no.2
• /
• pp.42-47
• /
• 1977

Experiment was conducted to find out the influence of nitrogen and potassium split application on the yield and physiology of rice plants in a sandy-gravel soil. Nitrogen and potassium mixed application, nitrogen split application, and potassium split application increased yield of rice by 22, 20, and 18%, respectively, compared to conventional fertilizer application. Nitrogen split application increased chlorophyll content and potassium split application increased root activity. Concentration of silica, magnesium, and calcium was increased by the mixed split application of nitrogen and potassium.

• Korean Journal of Ecology and Environment
• /
• v.49 no.1
• /
• pp.1-10
• /
• 2016

The increases of industrial and technological development and human activities have disturbed the balance of natural nitrogen (N) circulation. These phenomena have induced that large amounts of N are to be present in excess in air, soil and water environment. We investigated the effects of excess of reactive nitrogen ($N_r$) compounds on soil and water environment ecosystems through literature and case studies, and suggested the strategy of mitigating the acidification in soil and water ecosystems. $N_r$ moves to air, soil and water media, can be converted to different types, and interacts with other chemical compounds. As an efficient N management plan, the evaluation (application of monitoring and safety index) and the chemical restoration (research and development) of the acidification in soil and water environment ecosystems are required to minimize the effects of $N_r$ as well as policies to regulate the various emission sources and amounts of $N_r$.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2018.06a
• /
• pp.61-61
• /
• 2018

듀플렉스 스테인리스강은 페라이트와 오스테나이트 상이 공존하는 특징을 갖는다. 그러한 구조에 의해서 페라이트와 오스테나이트상의 장점을 동시에 갖는 특성이 있다. 높은 강도와, 우수한 내식성, 응력 부식 균열 그리고 낮은 니켈의 함량 때문에 안정적인 가격을 갖는 장점을 갖기 때문에 운송, 기름과 가스, 해양플랜트, 건축 그리고 높은 강도와 우수한 내식성이 필요한 분야에서 수요가 증가할 것으로 사료된다. 이러한 듀플렉스 스테인리스강의 형성에서 페라이트와 오스테나이트상의 균형과 내식성을 개선하기 위해 질소가 첨가된다[1,2]. 본 연구는 저니켈 듀플렉스 스테인리스강(STS 329 FLD)의 공식 형성 과정에서 질소의 함량이 공식 형성과 내식특성에 미치는 영향을 동전위분극, XPS(X-ray Photoelectron Spectroscopy) 그리고 GDOES(Glow Discharge Optical Emission Spectrometry)를 이용하여 규명하였다. GDOES를 이용하여 깊이별 원소 분포를 정량적으로 비교한 결과, 부동태막에서 질소는 기저에 비하여 증가하였고, 질소의 함량이 증가함에 따라 wt.% 또한 증가하였다. 이러한 부동태막의 깊이별 원소 분포특성이 내식특성과 공식의 크기에 미치는 영향을 동전위분극을 이용하였다. 질소의 함량이 증가하였을 경우, 부식전위는 증가하였으며, 부식전류는 감소하였다. 또한 부동태전류가 감소한 것을 확인할 수 있었다. 이러한 차이의 원인을 확인하기 위하여 XPS를 이용하여 질소의 화학적 상태를 확인하였다. 질소는 암모니아의 형태로 존재하는 것으로 확인되었다. 암모니아 상태로 부동태막에 존재함에 따라 공식이 형성될 때, 암모늄 화함물을 형성하여 공식 내부의 산성도를 낮춤으로써 공식의 형성이 억제된 것으로 사료된다. 또한 공식 이후의 표면을 관찰 할 경우 질소의 함량이 증가함에 따라 표면에서 공식이 거의 관찰되지 않았다.