• 한국환경농학회지
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• 제29권1호
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• pp.33-38
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• 2010

토양화학성을 고려한 기존의 토양검정 시비추천방법을 보완하기 워하여 논토양 유형별 질소시비기준을 설정하기 위하여 12개 벼 시험포장에서 토양유형별 질소검정시비량 시험을 실시하였다. 유형별 토양검정에 의한 질소시용량은 질소표준권장량 보다 많게 환산되었고, 질소수준별 회귀분석에 의한 최소 수량 생산시비량은 염해답에서 315 kg/10a, 사질답에서 168kg/10a로 최고와 최저시비량을 보였다. 유형별 질소흡수량은 질소시비량과 비례관계였고, 질소이용률은 미숙답에서 36.7%로 가장 높았으며, 질소시비량과 반비례 관계였다. 쌀의 식미치는 논토양 유형에 관계없이 무질소에서 높았고, 유형별로는 염해답에서 가장 낮았다. 시비효율지수와 환경지수 및 쌀 품질을 표준화하여 얻은 최적시비량은 보통답과 사질답에서는 토양검정 시비량의 1.0배, 미숙답과 염해답에서는 각각 0.92와 0.83배 했을 때 최적 시비량 수준을 보였다.

• Journal of the Korean Data and Information Science Society
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• 제15권4호
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• pp.845-853
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• 2004

This study is to adjust the focus on the statistical survey about the rates of application for the 2005 Susi second semester admission to Universities in Daegu, Kyungbook. The decrease of population for university admission and the change of paradigm of selecting a field of specialization in university will have an adverse effect on ratios of admission. This is very important to the future of university in Daegu, Kyungbook.

• 한국작물학회지
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• 제41권1호
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• pp.123-130
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• 1996

국내 쌀 생산비를 절감하여 국제경쟁력을 제고시키기 위한 일환으로 벼 담수표면직파재배에서 많이 발생하는 도상에 대한 기초연구로 담수표면직파재배에 있어서 파종량과 생장조절제 처리에 따른 내도복성과 수량성에 대한 시험을 하였던 바 그 결과를 요약하면 다음과 같다. 1. 파종량에 따른 입묘수는 60.9~143.4개/$m^2$의 분포를 보였으며, 립묘율은 71.7~76.1%로 양호한 경향이었다. 2. 파종량이 많을수록 간장이 길었으며, 생장조절제 KIM-112 처리에 의한 하위절간의 단축으로 간장 단축이 뚜렷하였고, 처리시기에 따라 단축정도는 각각 달랐다. 3. 생장조절제 KIM-112 처리는 엽각과 상위엽을 작게하여 직립화에 의한 수광태세가 개선되었으며, 또한 간기중이 증가하였으며 파종량이 많을수록 도복경감 효과가 컸다. 4. 줄기 좌절시 모멘트와 간직경은 파종량이 많을수록 감소하였으며 그 정도는 KIM-112 처리에서 훨씬 작았고, 단위면적당 이삭수는 파종량이 증가함에 따라 많아졌고, 등숙률과 천립중은 KIM-112처리에서 약간 높았다.

• 한국연초학회지
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• 제8권2호
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• pp.9-17
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• 1986

Effect of nitrogen rate with and without chance of Phosphorus and Potassium rate was investigated in a field experiment. Percentage of plant mortality after transplanting increased with N rates above 32.5kg/10a. The content of total nitrogen increased and postassium decreased slightly as the rates of applied N was increased, but the contents of total alkaloid and phosphorus were not affected at each growing stage. It was considered that the application of 17.5kg of P2O5 and 35.0kg of K2O Per 10a might be sufficient for high yield and good Quality. As the N rates being increased, the yield, value, contents of total alkaloid and total nitrogen of cured leaf increased However, the Brice per kg was not significantly different among 17.5 ~ 37.5kg / 10a of N rates. The application of 37.5kg/10a of N may be profitable for farm economy; but, the N application should be controlled 17.5~22.5kg/10a for the low nitrogen and alkaloid leaf.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2002년도 학술발표회 발표논문집
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• pp.473-476
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• 2002

The effect of fertiltzer application on ponded and percolation water in rice paddy were investigated at the experimental plots during irrigation period. We laid out three experimental plots such as 150% Excessive, 100% Standard and 70% Reduced. The concentration of T-N and T-P in ponded water were increased rapidly after application. The concentration of T-N and COD in percolated water increased with fertilizer application rates, while T-P concentration were almost constant.

• 한국초지조사료학회지
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• 제15권1호
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• pp.43-51
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• 1995

Tlis experiment was to study the effects of application rates of mineral N and cattle slurry on the dry matter yield and botanical compositions of Orchardgrass sward grown in 4 cuttings in a year. Annual rates of mineral N of O($N_0$), 120kg(($N_1$), 240kg(($N_2$) and 360kg/ha(($N_3$) were applied as urea, and cattle slurry applied at rates of O(($N_0=N_0$), $40m^3$($S_1$), $80m^3$(($S_2$) and $120m^3$($S_3$), suppling 120kg, 240kg and 360kgl ha, respectively. The results were summarized as follows; 1. The limiting annual application rates of mineral N and cattle slurry was estimated about 120kg/ ha. 2. The growth of Orchardgrass after the 3rd cut was decreased by summer depression. Consequently, the botanical compositions of Orchardgrass showed only 7.7% and 4.0% in 3rd and 4th cut, respectively. However, the 15 and 17 species of weeds originated in 3rd and 4th cut. 3. The botanical compositions of Amaranthus mangostanus in 3rd cut and Portulacea aleracea in 4th cut were greatly increased with application rates of cattle sluny. 4. Relative efficiency of cattle sluny for the dry matter production of Orchardgrass as compared to mineral N were 93.396, 99.5% and 113.6% in 120kg, 240kg and 360kglha at rates of cattle slurry, respectively.

• Journal of Biosystems Engineering
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• 제28권4호
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• pp.361-368
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• 2003

This study was intended to investigate the temporal and spatial variabilities of dry matter, nitrogen content, chlorophyll of paddy rice and yield caused by different rates of nitrogen application. An experimental field was divided into 45 plots of 3.48 ${\times}$ 12 m in size and application rate of nitrogen varied from 0 to 235% with an increment of 25% based on the standard rate of N-P$_2$O$_{5}$-K$_2$O=12-8-8 kg/10a. The measurements were made 8 times every 9-10 days after the transplanting. About 60 days after the transplanting, there exhibited little variabilities in the dry matter caused by different rates of nitrogen application. After that. however, there showed large variabilities and the dry matter increased with the application rate. The nitrogen content of paddy also increased with the application rate but it was inconsistent. After the tillering period, the nitrogen content remained constant. In the early stage of the tillering period the nitrogen content decreased in spite of increase in the dry matter. However. after a certain period of time it increased with the dry matter. There were little variabilities of chlorophyll after the transplanting. However, the SPAD increased with application rate of nitrogen as the paddy grew. After the tillering period SPAD was not affected by the different rates. More yield was obtained at the plots where larger nitrogen content was measured.d.

• Asian-Australasian Journal of Animal Sciences
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• 제29권8호
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• pp.1129-1135
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• 2016

Whole-crop wheat (Triticum aestivum L.) as forage has been extensively used in the world. In this study, the effects of N application rates on the yields, nutritive value and silage quality were investigated. The N application rates were 0, 75, 150, 225, and 300 kg/ha. The research results indicated that the dry matter yield of whole-crop wheat increased significantly with increasing N rate up to 150 kg/ha, and then leveled off. The crude protein content and in vitro dry matter digestibility of whole-crop wheat increased significantly with increasing N up to 225 kg/ha, while they no longer increased at N 300 kg/ha. On the contrary, the content of various fibers tended to decrease with the increase of N application. The content of lactic acid, acetic acid and propionic acid in silages increased with the increase of N rate (p<0.05). The ammonia-N content of silages with higher N application rates (${\geq}225kg/ha$) was significantly higher than that with lower N application rates (${\leq}150kg/ha$). Whole-crop wheat applied with high levels of N accumulated more nitrate-N. In conclusion, taking account of yields, nutritive value, silage quality and safety, the optimum N application to whole-crop wheat should be about 150 kg/ha at the present experiment conditions.

• Asian-Australasian Journal of Animal Sciences
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• 제24권7호
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• pp.965-973
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• 2011

Our objective was to determine the differences in the rate and extent of dry matter digestion between barley subjected to differing agronomic variables. Two malting barley varieties, Copeland and Metcalfe were seeded at rates of 200 and 400 plants/$m^2$. Each of these varieties received nitrogen fertilizer at rates of 0, 30, 60 and 120 kg/ha, resulting in a total of 20 different barley grain samples. Samples were ground through a 6mm screen and approximately 3 g of each weighed into 50 ${\mu}m$ Dacron bags and sealed. The bags were incubated in three ruminally cannulated Holstein cattle for periods of 0, 3, 6 and 24 h. Using the data obtained from these incubations, rates of digestion were able to be predicted. The soluble fraction ranged from 0.229-0.327, the slowly degradable fraction ranged from 0.461-0.656, and the undegradable fraction ranged from 0.038-0.299. The rates of digestion ranged from 0.127-0.165 $h^{-1}$ and the effective degradability ranged from 0.527-0.757. At the Canora location, the Copeland samples which received 120 kg/ha of nitrogen fertilizer had a significantly lower (p = 0.013) soluble fraction than the rest of the samples at that location. A significant interaction (p = 0.009) was seen between the seeding rate and nitrogen fertilizer application with samples from the Canora location, as well as significant differences (p = 0.029) between nitrogen application rates in samples from the Indian head location. The rate of digestion of samples from the Indian head location differed (p = 0.020) between the two seeding rates, with samples seeded at 200 seed/$m^2$ having a slightly higher rate of degradation. Differences in the effective degradability were seen between the different nitrogen application rates with samples from both the Canora and Indian head locations, as well as an (p = 0.004) interaction between the seeding rate and nitrogen fertilizer application rate. Although there was not a clear correlation between the different variables, both nitrogen application and seeding rate did have a significant effect on the rates and extent of digestion across each of the four locations.

• Journal of Ecology and Environment
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• 제35권4호
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• pp.307-311
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• 2012

This study was conducted to evaluate the dynamics of soil respiration (total soil and heterotrophic respiration) following fertilizer application in red pine forests. Fertilizer (N:P:K = 113:150:37 kg/ha), which reflects current practices in Korean forest, was applied in April 2011, and total soil and heterotrophic respiration rates were monitored from April 2011 to March 2012. Monthly variation of total soil and heterotrophic respiration rates were similar between the fertilizer and control treatments, as soil temperature was the dominant factor controlling the both rates. Total soil respiration rates during the study period were not significantly different between the fertilizer (0.504 g $CO_2\;m^{-2}\;h^{-1}$) and control (0.501 g $CO_2\;m^{-2}\;h^{-1}$) treatments. However, the proportion of heterotrophic respiration was higher in the fertilizer (78% of total soil respiration rates) than in the control (62% of total soil respiration rates) treatments. These results suggest that current fertilizer practices in Korea forest soil do not substantially affect total soil respiration rates.