• ALGAE
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• 제19권1호
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• pp.1-6
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• 2004

Carbon ($^{14}CO_2$) and nitrogen ($^{15}NH_4$ and $^{15}NO_3$) uptake were measured at two stations in the hypertrophic zone of the Seonakdong River, where Microcystis aeruginosa explosively bloomed in September 1998. Significant nitrogen limitation occurred in the period of Microcystis bloom, while phosphorus limitation was common in the river. The specific nitrogen ($NH_4$ + $NO_3$) uptake was 12-50 $\mu$mol mg chl-a$^{-1}$ hr$^{-1}$ at two stations, showing substantially higher than for any other freshwaters. The specific nirtogen uptake was higher at the GAR Station of the nitrogen-limited area and this high nirtogen uptake resulted in low $^{14}C:^{15}N$ atomic ratios of algal uptake. Carbon uptake was dependent upon irradiance, decreasing gradually toward the bottom in the euphotic zone, whereas the nitrogen uptake increased slightly toward the bottom. $NH_4$ preferable uptake against $NO_3$ was hardly discemilble due to the fact that it exceeded the $NH_4$ ambient concentraiton. The $^{14}C:^{15}N$ atomic ratios of algal uptake in the surface waters approached the Redfield C:N ratio.

• 한국작물학회지
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• 제49권2호
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• pp.89-93
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• 2004

This experiment was conducted to investigate the variation of nitrogen use efficiency, nitrogen uptake efficiency, physiological utilization efficiency and their relationships with growth characteristics in the 28 Korean rice cultivars. Nitrogen use efficiency of 28 rice cultivars was 47.74, nitrogen uptake efficiency was 0.71, and physiological utilization efficiency was 68.76 in average. Nitrogen use efficiency of rice cultivars had low variation ranged from 44.09 to 51.91, but nitrogen uptake efficiency were relatively high variation from 0.51 to 0.90, and physiological utilization efficiency was from 51.71 to 94.26. The high efficient group in nitrogen uptake efficiency whose value was calculated above 0.80 included Daeanbyeo, Seojinbyeo, Ansungbyeo, Dongjinbyeo, and Hwaanbyeo, while the low efficient group with below 0.60 was Kwanganbyeo, Sampyeongbyeo, Soorabyeo, and Hwasungbyeo. Hwasungbyeo, Sampyeongbyeo, Soorabyeo for physiological utilization efficiency were more efficient cultivars, while Daeanbyeo, Seojinbyeo, Ansungbyeo were less efficient cultivars. Nitrogen uptake efficiency had positive correlation coefficients between dry matter weight of plant ($0.842^{**}$), leaf area index ($0.761^{**}$), and leaf nitrogen content ($0.599^{**}$), respectively. Therefore, the dry matter weight of rice plant and leaf area index was important characters to evaluate nitrogen uptake efficiency in rice cultivars. Also, more efficient cultivar in nitrogen uptake had higher chlorophyll meter value, which was appeared dark green color.

• 한국유기농업학회지
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• 제13권2호
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• pp.211-221
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• 2005

This experiment was conducted to evaluate the effect of animal slurry on nitrogen uptake of hairy vetch and growth of chinese cabbage in cropping system. Hairy vetch was seeded on September 20 in 2003 . We examined the effect of cover crop(hairy vetch (Vicia villosa Roth) and slurry application(0, l00, 200kg N/ha) on yield and N uptake. Dry matter yield and nitrogen uptake of hairy vetch were measured. The chinese cabbage succeeding cover crop was harvested in 2004. The nitrogen uptake of hairy vetch was 84, 121, 148kg N/ha respectively, when the slurry application was 0, 100 and 200kg N/ha. In addition. N uptake of hairy vetch at the plot of 100kg and 200 kg N/ha slurry were 44% and 76% higher than that of the plot without slurry application respectively. Slurry application of hairy vetch could increase nitrogen uptake by application of green manure at the harvesting time. the content of organic matter and P-content of soil with hairy vetch plot was higher than that of fallow plot due to inhibition of soil erosion. The organic matter levels tend to improve with the addition of hairy vetch. Hairy vetch could improve soil quality by reducing erosion compared with bare fallow. The green manure of hairy vetch with animal slurry maintained soil nutrient and reduced nitrogen fertilizer of chinese cabbage. The hairy vetch residues decomposed rapidly releasing half of their residues within 40 days after burial. The yield of chinese cabbage was 90% in the plot of manure of hairy vetch compared with chemical fertilizer. The yield in the plot treated with green manure of hairy vetch and 50% of chemical fertilizer was reduced 5% less than that of chemical fertilizer. Therefore, it was estimated that the green manure of hairy vetch-chinese cabbage cropping system could reduce nitrogen chemical fertilizer as much as 84~148kgN/ha. the green manure of hairy vetch with animal slurry maintained soil nutrient and reduced nitrogen fertilizer of chinese cabbage.

• 환경영향평가
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• 제18권1호
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• pp.41-50
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• 2009

Using the "Statistical Yearbooks of Korean forestry", we assessed the uptake of nitrogen and base cations by Korean forest. Combined amount of base cations uptake by forest tress during its growth and that of at the time of harvest reached to 1,034 eq/ha/yr. The base cations uptake in the range of 900 ~ 1,100 eq/ha/yr occupied approximately 48.6% out of total. Coniferous forest in the range of 170 ~ 200 eq/ha/yr was 59.9%, deciduous forest in the range of 430 ~ 530 eq/ha/yr was 42.6%, and mixed forest in the range of 270 ~ 370 eq/ha/yr was 35.7% out of total. Deciduous forest recorded higher uptake rate of nitrogen and base cation than coniferous forest in Korea. Combined amounts of nitrogen uptake by forest tress during growth and that at the time of forest, was 1,108 eq/ha/yr and nitrogen uptake was in the range of 1,000 ~ 1,200 eq/ha/yr, Within Korea, forest with nitrogen uptake in the range of 1,000 ~ 1,200 eq/ha/yr account for 45.7% of the entire country. Locations in the range of 320 ~ 390 eq/ha/yr occupied 43.9% of all coniferous forest while deciduous forest in the range of 470 ~ 570 eq/ha/yr was 40.4% of total deciduous forest. As for mixed forest in the range of 270 ~ 370 eq/ha/yr, it occupied 35.9% of all mixed forest of Korea.

• 한국토양비료학회지
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• 제7권3호
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• pp.147-154
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• 1974

질소(窒素)의 정조생산효율을 높이는 방법(方法)을 찾고자 정조수량(精租收量)(Y) 질소효율(E) 및 질소흡수량(窒素吸收量)(N)간(間)의 상호관계(相互關係)를 우리나라와 일본자료(日本資料)에 의(依)하여 찾아보았다. E와 N간(間)의 관계는 수개(數個) 계층(階層)으로 구분(區分)할 수 있었으며 각계층내(各階層內)에서 Y=EN=(b-aN)N 관계(關係)가 성립(成立)되었으며 여기서 b는 E의 이론적최대치(理論的最大値)였고 a는 이론적(理論的) 최대수량(最大收量)에서의 E/N치(値)였다. 수도고수량(水稻高收量) 연구(硏究)에 있어 현재(現在)의 기술(技術)은 효율 56.8에 이르렀으며 이때 질소흡수량(窒素吸收量)은 15.5kg이었다. 장래(將來)의 목표(目標)는 질소(窒素) 흡수량(吸收量) 17kg에서 효율 63에 이르는 것으로 나타났다. 일본독농가(日本篤農家)에서는 이 수준(水準)에 이미 도달(倒達)했을 가능성이 있다. 질소효율(窒素效率)의 증가(增加)없이는 고수량(高收量)을 달성(達成)할 수 있는 질소흡수(窒素吸收)가 증가(增加)되지 않는 것으로 보였다. 토양질소(土壤窒素)의 효율(效率)과 흡수량(吸收量)의 증대(增大)가 전체질소(全體窒素)의 효율증대에 필수요건(必須要件)으로 나타났다.

• 한국작물학회지
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• 제58권3호
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• pp.213-219
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• 2013

A field study was conducted to understand nitrogen use efficiency of high yielding Japonica rice varieties under three levels of nitrogen fertilizer (90, 150 and 210 kg N $ha^{-1}$) in Iksan, Korea. Two high yielding rice varieties, Boramchan and Deuraechan, and an control variety, Dongjin2, were grown in fine silty paddy. Nitrogen use efficiencies (NUE) were 83.3, 56.3, and 41.2 in 90, 150, and 210 kg N $ha^{-1}$ fertilizer level, respectively. Total nitrogen uptake varied significantly among nitrogen levels and varieties. Variety Dongjin2 showed the highest nitrogen uptake efficiency (NUpE), while Boramchan and Deuraechan showed higher nitrogen utilization efficiency (NUtE). However, Nitrogen harvest index (NHI) was higher in Boramchan (0.58) than Deuraechan (0.57) and Dongjin2 (0.53). Rough rice yield showed linear relationship with total nitrogen uptake ($R^2$=0.72) within the range of nitrogen treatments. Boramchan produced significantly higher rough rice yield (8546 kg $ha^{-1}$) which mainly due to higher number of panicles per $m^2$ compared to Deuraechan (7714 kg $ha^{-1}$). Deuraechan showed higher number of spikelets per panicle, but showed lower yield due to lower number of panicle per $m^2$. Rice varieties showed different nitrogen uptake ability and NUE at different nitrogen level. Plant breeders and agronomist should take advantage of the significant variations and relationships among grain yield, NUpE, and NUE.

• 한국작물학회지
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• 제46권1호
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• pp.1-5
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• 2001

Field experiment was conducted during 1993-94 season to determine the pattern of nutrient uptake and productivity of maize/sweet potato intercropping system. Four levels of nitrogen (0, 50, 100 and 150kg N ${ha}_{-1}$) and four levels of potassium (0, 40, 80 and 120kg $K_2$O ${ha}_{-1}$) formed treatment variables. Plants were sampled periodically to determine dry matter and tissue concentrations of N and K in the individual plant components of intercropped maize and sweet potato. Nitrogen and potassium fertilizer did not interact significantly to nutrient uptake by any plant parts of intercropped maize and sweet potato. But application of N fertilizer independently enhanced N uptake in all the plant parts of maize and sweet potato. The uptake of N in leaf, leaf sheath, stem, husk, and cob of maize increased upto 90 days after planting (DAP) but grain continued to accumulate N till its maturity. Sweet potato exhibited a wide variation in N uptake pattern. Sweet potato leaf shared the maximum uptake of N at 50 DAP which rapidly increased at 70 DAP and then declined. Declination of N uptake by petiole and stem were observed after 120 DAP whereas N uptake by tuber increased slowly upto 90 DAP and then rapidly till harvest. Rate of applied K had very little effect on the uptake patterns in different components of intercropped maize. Pattern of K uptake by leaf, petiole and stem of sweet potato showed almost similar trend to N uptake. But uptake of K by tuber increased almost linearly with the K application. Pattern of N and K uptake by grain and tuber paralleled the grain yield of maize and sweet potato respectively. Intercropped productivity of maize and sweet potato found to be better by the application of 100kg N and 120 kg $K_2$O ${ha}_{-1}$

• 한국토양비료학회지
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• 제7권2호
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• pp.119-125
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• 1974

삼요소시험(三要素試驗)(1967~69)을 중심(中心)으로 정조수량등급별(正租收量等級別)로 N, P, K, Si의 흡수량(吸收量)과 이들의 정조생산효율(正租生産効率) 및 전이율(轉移率)을 본결과 다음과 같다. 1) 수량증가(收量增加)에 따른 각양분(各養分)의 요구도(要求度)는 유사(類似)한 비율(比率)로 증가(增加)하였으나 규산(珪酸)이 가장 변화(變化)가 컸다. 2) 질소효율(窒素効率)이 낮은(46kg/Nkg) 삼요소(三要素)시험에서는 수량(收量)이 증가(增加)할수록 효율(効率)과 전이율(轉移率)이 증가(增加)하는 경향(傾向)이다. 3) 질소흡수량(窒素吸收量)이 증가(增加)할수록 질소(窒素)의 정조생산효율(正租生産効率)이 감소(減少)하였으며 이감소정도는 비종(肥種) 및 품종(品種)에 따라 크게 다르다. 질소효율(窒素効率)은 식질(埴質)에서보다 수량(收量)이 높은 사양토(砂壤土)에서 높았다. 4) 질소(窒素)의 정조생산효율(正租生産効率)은 질소(窒素)의 인으로의 전이율(轉移率)과 정상관관계(正相關關系)였다. 5) 다수확(多收穫)은 질소효율(窒素効率)이 50정도에서 머문채 질소흡수량(窒素吸收量)만을 증가(增加)시켜 이루어지고 있다. 6) 질소효율(窒素効率)의 저하(低下)가 저수(低收)의 큰요인(要因)으로 보였다. 7) 삼요소시험(三要素試驗)에서 인산(燐酸)의 정조생산(正租生産) 효율(効率)이 상당히 낮은 편인데 인산(燐酸)의 토양환원(土壤還元)에 의(依)한 과다흡수(過多吸收)에 기인(基因)하는 것 같다.

• 한국작물학회지
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• 제48권5호
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• pp.355-360
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• 2003

The responses of six mungbean [Vigna radiata (L.) Wilczek] varieties to Rhizobium inoculation on number and dry weight of nodules, nitrogenase activity of root nodule bacteria, dry weight of shoot and root, nitrogen content, and uptake by shoot were investigated. The mungbean varieties were BARI Mung-2, BARI Mung-3, BARI Mung-4, BARI Mung-5, BINA Moog-2, and BU Mung-1. Two-third seeds of each variety were inoculated with Rhizobium inoculant and the remaining one-third seeds were kept uninoculated. Rhizobium strains TAL 169 and TAL 441 were used for inoculation of seeds. Inoculation of seeds with Rhizobium strains significantly increased nodulation, nitrogenases activity, dry matter production, nitrogen content, and uptake by shoot of the crop compared to uninoculated control. There was positive correlation among the number and dry weight of nodules, nitrogenase activity, dry weight of shoot and root, nitrogen content, and uptake by shoot of the crop. It was concluded that BARI Mung-4 in association with Rhizobium strain TAL 169 performed best in recording nodulation, nitrogenase activity, dry matter production, and nitrogen uptake by shoot of mungbean.

• 한국작물학회지
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• 제48권5호
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• pp.381-387
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• 2003

Winter hairy vetch (HV) can be used as green manure with conventional tillage system (CT), in which chemical N fertilizer required for cultivation of sub-sequent com could be fully saved, or as cover crop with no-tillage system (NT) in which soil could be protected from erosion, control of weed, and the reduction of N fertilizer application. This experiment was carried out to compare the enrichment of soil mineral nitrogen (SMN) at corn root zone, and the changes of com growth and N uptake according to HV amounts (winter fallow, above-ground HV removed, intact HV, and HV added from aboveground HV removed) under two tillage systems in the upland field of National Crop Experiment Station, Suwon, Korea in 1996. HV cultivation during winter decreased SMN a little at com planting. HV incorporation with CT increased SMN rapidly during early growth stage according to rapid decomposition of Hv. SMN by HV cover with NT was increased slowly and its increase was higher in the surface soil (soil layer 0-7.5cm) compared to deep soil layer 7.5-22cm. Com growth and N status at corn silking stage, com yield and N uptake at harvest were increased in proportion to aboveground HV amounts regardless of tillage system. Average hairy vetch nitrogen (HV-N) uptake efficiency by com was 10% higher with CT than with NT in which average HV-N uptake efficiency was 43 %. Corn yields were not different between two tillage systems, but corn N uptake was increased by 33 kgN/ha more with CT than with NT due to the increase of corn N concentration. The increase of SMN and com N uptake from HV cover with NT could not be disregarded though those with CT were higher than with NT