• 한국패류학회지
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• 제14권2호
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• pp.167-172
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• 1998

As a preliminary study, effects of environmetal pollutants on propagation of freshwater microalgae, Cryptomonas ovata and feeding rate of Corbicula leana were investigated at 20${\pm}$1$^{\circ}C$, over 20 days after treatment of pollutants, glucose, complex fertilizer and NH4Cl. Number of C. ovata in control group was increased from 38${\times}$104 cell/ml to 1.910${\times}$104 cell/ml after 20 days cultivation in Sorokin-Krauss medium. Increments of cell number in experimental groups treated with glucose, complex fertilizer and NH4Cl were higher than that of control group. The higher propagation rate of C.ovata was observed when 30 mg/l of glucose treated, 120 mg/l of complex fertilizer treated, and 4 mg/l of NH4Cl treated, compared with other concentrations in each pollutant treated group. The feeding rates of large size group of C. leana which fed with a living organism, C. ovata in each experimental group were higher than small size group, and slightly reduced with the increase of pollutant concentrations. The feeding rates were not significantly different between any concentrations of the pollutant, and among experimental groups treated with glucose, complex fertilizer and NH4Cl.

• 한국연초학회지
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• 제14권2호
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• pp.151-158
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• 1992

Field experiment was conducted to investigate the effects of stalk position, compound fertilizer application rate (N-P2O5-K2O : 10-10-20 : 75, 100, 125kg/03), paddy and upland soil and varieties, NC82 &KF103, on nonvolatile organic and higher fatty acids of flue-cured tobacco. Followed by stalk position, malic, citric, malonic and succinic acid contents were significantly increased with higher stalk position, but oleic and linoleic acid contents were decreased with higher stalk position. The higher application rate of compound fertilizer results in increasing citric, malic, malonic and succinic acid contents, but the contents of higher fatty acids were not significantly influenced by fertilizer application rate. The cured leaf cultivated in paddy soil was higher citric and malic acid contents than in upland soil, but the contents of higher fatty acids have no difference between paddy and upland soil. The variety of KF103 was higher citric and linoleic acid contents than that of NC82, but the contents of higher fatty acids have no difference between varieties.

• 아시안잔디학회지
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• 제21권2호
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• pp.177-182
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• 2007

축구장의 식재지반이 모래로 조성될 경우 낮은 보비력과 높은 용탈율로 인해 시비관리의 조정이 필요하다. 본 실험의 목적은 PVC관을 이용한 경기장 유사모형 실험구에서 캔터키 블루그래스에 있어서 완효성비료의 생육 효과를 비교 실험하였다. 잔디의 색깔, 균일도, 생육, 지상부 생체량과배출수의 질산의 유출량을 몇 가지 다른 생육상과 네 번의 유사 강우 시험 시 행하였다. 실험 결과 요소의 성분 유출량이 가장 높았고 공시 완효성비료는 가장 낮았다. 이 완효성 비료는 다른 공시 잔디비료에 비해 14일간, 요소보다는 28일간 잔디의 품질 면에서 비효가 지속되었다. 또한 이 완효성비료는 잔디의 웃자람과 잔디깎기에 소요되는 시간을 줄일 수 있었다. 질산태 질소의 유출에 있어서도 잔디의 조성 초반기에 50% 정도를 감소 시켰다.

• 한국토양비료학회지
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• 제48권4호
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• pp.246-254
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• 2015

This study explored the effect of rainfall pattern and soil characteristics on water management in rice paddy fields, using a soil water balance model, BUDGET. In two sites with different soil textural group, coarse loamy soil (Gangseo series) and fine soil (Hwadong series), respectively, we have monitored daily decrease of water depth, percolation rate, and groundwater table. The observed evapotranspiration (ET) was obtained from differences between water depth decrease and percolation rate. The root mean square difference values between observed and BUDGET-estimated ET ranged between 10% and 20% of the average observed ET. This is comparable to the measurement uncertainty, suggesting that the BUDGET model can provide reliable ET estimation for rice fields. In BUDGET model of this study, irrigation requirement was determined as minimum water need for maintaining water-saturated soil surface, assuming 100 mm of bund height and no lateral loss of water. The model results showed different water balance and irrigation requirement with the different soil profile and indicated that minimum percolation rate by plow pan could determine the irrigation requirement of rice paddy field. For the condition of different rainfall distribution, the results presented different irrigation period and amounts, representing the importance of securing water for irrigation against different rainfall pattern.

• 한국환경농학회지
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• 제30권2호
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• pp.99-104
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• 2011

BACKGROUND: Application of urea may increase $CO_2$ emission from soils due both to $CO_2$ generation from urea hydrolysis and fertilizer-induced decomposition of soil organic carbon (SOC). The objective of this study was to investigate the effects of increasing urea application on $CO_2$ emission from soil and mineralization kinetics of indigenous SOC. METHODS AND RESULTS: Emission of $CO_2$ from a soil amended with four different rates (0, 175, 350, and 700 mg N/kg soil) of urea was investigated in a laboratory incubation experiment for 110 days. Cumulative $CO_2$ emission ($C_{cum}$) was linearly increased with urea application rate due primarily to the contribution of urea-C through hydrolysis to total $CO_2$ emission. First-order kinetics parameters ($C_0$, mineralizable SOC pool size; k, mineralization rate) became greater with increasing urea application rate; $C_0$ increased from 665.1 to 780.3 mg C/kg and k from 0.024 to 0.069 $day^{-1}$, determinately showing fertilizer-induced SOC mineralization. The relationship of $C_0$ (non-linear) and k (linear) with urea-N application rate revealed different responses of $C_0$ and k to increasing rate of fertilizer N. CONCLUSION(s): The relationship of mineralizable SOC pool size and mineralization rate with urea-N application rate suggested that increasing N fertilization may accelerate decomposition of readily decomposable SOC; however, it may not always stimulate decomposition of non-readily decomposable SOC that is protected from microbial decomposition.

• 한국작물학회지
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• 제50권spc1호
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• pp.37-40
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• 2005

중산간지에서의 질소 시비량(0, 5, 7, 9, 11, 14, 17kg/10a)이 쌀의 품질에 미치는 영향을 검토하기 위하여, 3가지 품종(상미벼, 화영벼, 주남벼)을 대상으로 하여, 2개년간의 시험결과를 요약하면 다음과 같다. 1. 식미치는 질소시비량과 품종과의 상호작용 효과가 있었다. 즉 주남벼의 경우는 질소시비량에 따른 식미치의 차이는 없었으나, 화영벼의 경우는 질소 무비구가 5, 7, 17kg/10a 시비구보다 식미치가 높았으며, 상미벼의 경우는 7kg 시비구가 9, 11, 14, 17kg 시비구보다, 0, 5kg 시비구가 14, 17kg/10a 시비구보다 식미치가 높았다. 결과적으로 식미치는 품종에 따라 질소시비량에 대해 다르게 반응하는 것으로 나타났다. 2. Amylose 함량은 질소시비량간의 유의차는 인정되지 않았으나, 품종간의 Amylose 함량은 차이가 있어 상미벼<화영벼<주남벼 순으로 그 함량이 낮았다. 3. 단백질의 함량에서는 질소시비량과 품종간의 상호작용 효과가 인정된바, 주남벼와 화영벼의 경우는 질소시비량에 따른 차이가 없었고, 상미벼는 질소시비량이 적을수록 단백질의 함량이 낮았다. 4. 완전미와 백미의 수량은 질소시비량이 증가할수록 높았고, 품종간의 차이는 없었다. 5. 종전의 표준시비량인 질소 11kg/10a 시비구와 고품질 쌀 생산을 위해 새롭게 추천된 9kg시비구간의 쌀의 품질에 유의차는 인정되지 않았다. 6. 본 시험의 결과를 종합하면, 질소시비량에 따른 쌀의 품질은 품종에 따라 그 반응의 차이가 있어, 상미벼는 7kg/10a, 화영벼는 11kg, 주남벼는 14kg의 질소시비 수준에서 품질이 우수하고 수량이 높았다.

• 한국토양비료학회지
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• 제15권3호
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• pp.194-198
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• 1982

1974년(年)부터 1981년(年)까지의 연초경작지별(煙草耕作地別) 각종(各種) 비료시험성적(肥料試驗成績)을 수집(蒐集), 정리(整理)하여 비옥도(肥沃度)가 상이(相異)한 경작지토양(耕作地土壤)에서의 무비구 수량별(收量別) 표준시비량(標準施肥量)(10-15-20, 125kg/10a) 시비시(施肥時)의 잎담배 수량(收量) 및 품질(品質)과의 관계를 검토(檢討)하였다. 무비구 수량(收量)이 높은 (비옥도(肥沃度)가 높은) 토양(土壤)일수록 수량(收量)은 대수곡선적인 증가를 보이나 품질(品質)은 저하(低下)하는 유의성(有意性)있는 상관을 보였다. 표준시비량(標準施肥量)이 적용(適用)되는 적정비옥도(適正肥沃度)는 무비구 수량(收量)이 81kg/10a되는 비옥도(肥沃度)를 갖는 토양(土壤)이며, 무비구 수량(收量)이 이보다 많은 경작지(耕作地)에서는 현시비추천량(現施肥推薦量)이 적량인 것으로 판단된다. 따라서 무비구 수량(收量)을 기준(基準)으로 적정시비량(適正施肥量)을 추정(推定)할 수 있을 것으로 기대(期待)되며, 더 나아가서 무비구 수량(收量)을 지배(支配)하는 환경요인(環境要因) 및 토양이화학적(土壤理化學的) 요인(要因)이 밝혀지면 이 인자(因子)로써 적정시비량(適正施肥量)을 추천(推薦)할 수 있는 평가방법이 구명(究明)될 것이다.

• 한국토양비료학회지
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• 제34권3호
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• pp.153-157
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• 2001

To evaluate the effect of liquid pig manure application, the growth and yield of rice and the quality of infiltration water were investigated with application of different amounts of liquid manure. At this study, liquid pig manure was treated with 100, 200, 300 and 400% of recommending nitrogen fertilizer level, respectively. Liquid manure with application rate more than 200% of recommending N fertilizer level (11kg) caused to increase of plant height and number of tiller at panicle formation stage, but it caused the plant disease and pest and plant lodging. In those treatment, number of panicles per hill and number of spikelets per panicle were increased, but yield of rice was less than chemical fertilizer treatment due to low rate of ripeness and 1,000 grain weight. $NO_3-N$ concentration in infiltration water sample collected at 90 cm of soil depth was increased with increasing application amount of liquid manure. With liquid manure application more than 200% of recommending N fertilizer level, it affected negatively on yield and environment such as groundwater quality.

• 한국식품저장유통학회지
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• 제5권2호
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• pp.123-126
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• 1998

This study was carried out investigate to optimum levels of nitrogen and phosphate fertilizer to get a higher yield and a quality of an onion(Allium Cepa L.) from 1993 to 1994. Three fertilizer levels were applied with 120, 240 and 360kg/ha of nitrogen and 100, 200 and 300kg/ha of P2O5 during the onion growing season. After harvesting the onion, it was storaged at given deposit. The growth and yield of the onion were better at the fertilizer levels of both 240 and 360kg/ha of nitrogen and of both 200 and 300kg/ha of P2O5 than at the level of 120kg/ha in nitrogen and 100kg/ha of P2O5. The content of total nitrogen and P2O5 in plant was decreased with reduced application levels of nitrogen and phosphate fertilizer. The rotting rate was higher at the levels of both 360kg/ha in nitrogen and 300kg/ha in P2O5 than the other treatment during the storage period. The sprouting rate tended to be high at 240kg/ha of nitrogen and 100kg/ha of P2O5.

• 한국환경농학회지
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• 제19권5호
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• pp.375-381
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• 2000

Quantifying the changes of soil microbial biomass and activity of enzymes are important to understand the dynamics of active soil C and N pools. The dynamics of soil microbial biomass C and N and the activity of enzymes over entire growth period of soybean-(Glycine max (L) Merr.)-wheat (Triticum aestivum L.) sequence on a Typic Haplustert as influenced by organic manure and inorganic fertilizer N were investigated in a field experiment. The application of farmyard manure at 4 to 16 $Mg{\cdot}ha^{-1}\;y^{-1}r^{-1}$ along with fertilizer nitrogen at 50 or 180 $kg{\cdot}ha^{-1}$ increased the mean soil microbial biomass from 1.12 to 2.05 fold over unmanured soils under soybean-wheat system. Irrespective of organic and chemical fertilizer N application, the soil microbial biomass was maximum during the first two months at active growing stage of the crops and subsequently declined with crop maturity. The mean annual microbial activity was significantly increased when manure and chemical fertilizer at 8 $Mg{\cdot}ha^{-1}$ and 50/180 N $kg{\cdot}ha^{-1}$, respectively were applied. The C turnover rate decreased by 47 to 72 % when the level of farmyard manure was increased from 4 to 8 and 16 $Mg{\cdot}ha^{-1}$. There were significant correlations between biomass C, available N, dehydrogenase, phosphatase and yield of the crops.