• Journal of Animal Science and Technology
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• 제47권3호
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• pp.481-490
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• 2005

Nitrate contamination in water system is a critical environmental problem caused by excessive application of chemical fertilizer and concentration of livestock. In order to prevent further contamination, therefore, it is necessary to understand the origin of nitrate in nitrogen loading sources and manage the very source of contamination. The objective of this study was to examine the nitrate contamination sources in different agricultural system by using nitrogen isotope ratios. Groundwater and runoff water samples were collected on a monthly basis from February 2003 to November 2003 and analyzed for nitrogen isotopes. The nitrate concentrations of groundwater in livestock fanning area were higher than those in conventional and organic fanning area and exceeded the national drinking water standard of 10mg N/ l. The ${\delta}^{15}N$ranges of chemical fertilizer and animal manure were - 3.7${\sim}$+2.3$\textperthousand$ and +12.5${\sim}$26.7$\textperthousand$, respectively. The higher ${\delta}^{15}N$ of animal manure than those of chemical fertilizer reflected isotope fractionation and volatilization of '''N. The different agricultural systems and corresponding average nitrate concentrations and ${\delta}^{15}N$ values were: conventional farming, 5.47mg/e, 8.3$\textperthousand$; organic fanning, 5.88mg/e, 10.1$\textperthousand$; crop-livestock farming, 12.5mg/e, 17.7%0. These data indicated that whether conventional or organic agriculture effected groundwater and runoff water quality. In conclusions, relationship between nitrate concentrations and ${\delta}^{15}N$ value could be used to make a distinction between nitrate derived from chemical fertilizer and from animal manure. Additional investigation is required to monitor long-term impact on water quality in accordance with agricultural systems.

• 한국토양비료학회지
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• 제19권2호
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• pp.139-145
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• 1986

담배식물이 흡수한 질산태질소가 조직중(組織中)에서 환원 되므로서 양(陽)이온과 음(陰)이온성분간(成分間)의 평형(平衡)에 미치는 영향을 구명하기 위하여 질소원(窒素源)을 달리한 배양액(培養液)으로 재배(栽培)하면서 무기(無機) 양음(陽陰)이온총량차이(總量差異)를 조사하고 질소환원(窒素還元) 및 유기산함량(有機酸含量)의 변화(變化)와 이온총량차이(總量差異)와의 관계(關係)를 검토(檢討)한 결과(結果) 1. $NO_3-N$ 배양액에서 자란 식물은 $NH_4-N$ 배양액의 것보다 양(陽)이온총량(總量)이 높았다. 무기음(無機陰)이온총량(總量)은 $NO_3+NH_4$혼합배양액(混合培養液)에서 가장 높게 나타났으나 $NO_3-N$ 배양액에서 가장 낮아서 무기 양음(陽陰)이온총량차이(總量差異)가 가장 컸고 $NH_4{^+}$가 함유된 배양액에서는 무기양음이온 총량차이가 비슷하여 무기이온으로서 거의 이온균형(均衡)이 유지(維持)되었다. 2. 식물체중(植物體中) 유기산(有機酸)은 malic acid의 분포가 가장 컸으며 $NO_3-N$ 배양액식물은 유기산(有機酸)이 다량함유(多量含有)되어 있으나 $NH_4-N$ 또는 혼합배양액(混合培養液)의 것은 거의 검출(檢出)되지 않았다. $NO_3-N$ 배양액식물(培養液植物)은 유기산총량(有機酸總量)이 무기음(無機陰)이온 총량(總量)보다 초과(超過)되어 유기산(有機酸)에 의한 이온균형(均衡)비율이 크나 $NH_4-N$ 배양액식물은 이온균형(均衡)에 차지하는 유기산(有機酸)비율이 극히 소량이었다. 3. $NO_3-N$식물(植物)은 질산환원(窒酸還元)이 왕성하게 진행되므로서 유리(遊離)된 양(陽)이온과의 이온균형(均衡)을 위하여 유기산(有機酸)이 다량(多量) 함유(含有)되었다.

• BMB Reports
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• 제38권4호
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• pp.468-473
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• 2005

The energetics of nitrate uptake by intact cells of the halotolerant cyanobacterium Aphanothece halophytica were investigated. Nitrate uptake was inhibited by various protonophores suggesting the coupling of nitrate uptake to the proton motive force. An artificially-generated pH gradient across the membrane (${\Delta}pH$) caused an increase of nitrate uptake. In contrast, the suppression of ${\Delta}pH$ resulted in a decrease of nitrate uptake. The increase of external pH also resulted in an enhancement of nitrate uptake. The generation of the electrical potential across the membrane ($\Delta\psi$) resulted in no elevation of the rate of nitrate uptake. On the other hand, the valinomycin-mediated dissipation of $\Delta\psi$ caused no depression of the rate of nitrate uptake. Thus, it is unlikely that $\Delta\psi$ participated in the energization of the uptake of nitrate. However, $Na^+$-gradient across the membrane was suggested to play a role in nitrate uptake since monensin which collapses $Na^+$-gradient strongly inhibited nitrate uptake. Exogenously added glucose and lactate stimulated nitrate uptake in the starved cells. N, N'-dicyclohexylcarbodiimide, an inhibitor of ATPase, could also inhibit nitrate uptake suggesting that ATP hydrolysis was required for nitrate uptake. All these results indicate that nitrate uptake in A. halophytica is ATP-dependent, driven by ${\Delta}pH$ and $Na^+$-gradient.

• 한국초지조사료학회지
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• 제20권2호
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• pp.77-84
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• 2000

Eight-week old perennial ryegrass (Lolium perenne L. cv. Reveille) plants were exposed to different NO3-concentrations or osmotic stress with NaCI. Previously labeled "N was chased during 14 days of non-labeled'NO3 feeding in order to investigate NO3 metabolism in relation to osmoregulation. The short termmeasurement of osmotic potential showed that the extemal concentration of Nos- had not great effect on theosmotic potential, but that osmotic adjustment was observed in NaCl-treated plants. Total uptake of NO 3 - waslargely increased by increasing supply level of NO3 while it was depressed by exposing to osmotic stress.Nitrate reduction increased to more than 29% by increasing extemal NO,- concentration from 1 mM to 10mM. When osmotically stressed with NaCI, nitrate reduction was depressed to about 37% as compared to thecontrol. The decrease in translocation of reduced N into leaves was also observed in NaCl exposed plants. Inthe medium exposed to 10 mM NO,., osmotic contribution of nitrate to cumulative osmotic potential wasdecreased, and it was osmotically compensated with soluble carbohydrate. When osmotically stressed withNaC1, the contribution of chloride was much higher than that of nitrate. The present data indicate that N03-in plant tissues, factually affected by the assimilation of this ion, plays an active role in osmotic regulation incorrelation with other osmotica such carbohydrate and chloride.(Key words : Nitrate metabolism, Osmotic stress, Nitrate supply level, Osmoregulation)ate supply level, Osmoregulation)

• 한국환경농학회지
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• 제21권1호
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• pp.69-73
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• 2002

질산태 질소의 일중 농도 변화와 단기간의 저온 처리가 질산태 질소의 흡수 및 농도에 미치는 영향을 살펴보고자 상추 (Lactuca sativa L.)를 공시 작물로 하여 온실에서 수경 재배하였다. 질산태 질소의 농도는 엽신에 비하여 주맥에서 일중 지속적으로 2배 이상 높았으며, 질산태 질소의 일중 변화는 14:00까지 지속적으로 감소하여 최저치 (8.7 mg-N/GDW)를 나타낸 후 다시 증가하였다. 질산태 질소의 일중 흡수량은 11:00$\sim$17:00에 평균 4.8 mg-N/GDW-Root/hr로 최대치를 나타내었다. 단기간의 저온 처리는 엽의 질산태 질소의 농도를 14$\sim$18%, 질산태 질소의 흡수량을 50$\sim$55%를 감소시켰다. 이러한 결과는 수확 전 단기간의 저온처리가 상추 잎의 질산태 질소함량을 낮출 수 있는 방법으로 응용될 수 있음을 보여준다.

• 한국대기환경학회지
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• 제11권1호
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• pp.37-44
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• 1995

Concentration of particulate nitrate classified by formation mechanism and particle diameter in ambient air was determined from Feb. to Oct. 1993. Sampling was carried out using a two-stage Andersen air sampler at the top of a five-story building located at Kon-Kuk University in seoul. Concentration of N $H_{4}$N $O_{3}$ in TSP was measured by pyrolysis of sample filters at 160.deg.C for 1hr. concentration of N $H_{4}$N $O_{3}$ was higher in winter time compared with that in summmer time. Also, concentration of N $H_{4}$N $O_{3}$ was higher in fine particles compared with that in coarse particle. The range of N $H_{4}$N $O_{3}$ concentration was between 2.9 and 9.9.mu.g/ $m^{3}$. Weight fraction of N $H_{4}$N $O_{3}$ in total particulate nitrate was 31.1 .sim. 59.5%, and weight fraction of N $H_{4}$N $O_{3}$ in TSP was 2.1 .sim. 11.2%. Concentration of NaN $O_{3}$, which originated from sea salt, was highest in spring time and lowest in summer time,and the concentration range was between 0.1 and 0.7.mu.g/ $m^{3}$. NaN $O_{3}$/TSP ratio was very low (0.1 .sim. 0.4%) indicating that the portion of NaN $O_{3}$in TSP was negligible. Concentration of particulate nitrate originated from soil was 2.4 .sim. 2.9.mu.g/ $m^{3}$. Weight fraction of that in total particulate nitrate was 14.0 .sim. 37.1%.

• 한국토양비료학회지
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• 제30권1호
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• pp.29-34
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• 1997

본 연구(硏究)는 수경재배토마토에 있어서, 음(陰)이온이 무기양분흡수(無機養分吸收) 및 식물체의 원소조성(元素組成)에 미치는 영향을 구명하고자 수경재배의 주요 질소원으로 사용하고있는 $NO_3-N$의 영향에 관해 검토하였다. 토마토(TVR-2)는 파종후 24일에 정식하고 정식후 126일에 재배를 종료하였다. 배양액은 일본원시(園試)표준액을 기본조성(基本組成)으로하여 $NO_3-N$농도 8, 16, 24, 32cmol/l 처리구를 설정하고, 정식후 33일에 양액탱크용량 150l, 베드크기 $90{\times}90{\times}5cm$에 8주를 정식하여 재배하고, 재배종료기의 식물체를 화방별(花房別) 기관별(器官別)로 분획채취(分劃採取)하여 건물중을 평량한 후 무기성분(無機成分)을 분석 검토 하였다. 엽신(葉身)과 엽병(葉柄)의 건물중은 $NO_3-N$농도가 높을수록 증가 하였으나, 과실의 건물중은 $NO_3-N$농도 16cmol/l 처리구가 가장 높았다. 생식기관(生殖器官)에 대한 영양기관(營養器官)의 건물중비율(乾物重比率)은 $NO_3-N$농도 16cmol/l 처리구가 가장 낮았고, $NO_3-N$처리농도가 증가함에 따라 높아졌으며, 과실수량은 $NO_3-N$농도 16cmol/l 처리구가 가장 많았다. $NO_3-N$처리농도가 증가함에 따라, 엽신(葉身)과 엽병중(葉柄中)의 전질소, $NO_3-N$, Ca 및 Na농도가 증가하였으며, $NO_3-N$ 농도 24 및 32cmol/l 처리구에서 K, P, S 및 Cl농도가 감소하는 경향을 나타냈다. 이상의 결과로부터 수경재배토마토에 있어서 $NO_3-N$의 적정농도는 생육시기에따라 다르며 영양생장기(營養生長期)에는 8cmol/l가, 생식생장기(生殖生長期)에는 16cmol/l가 적절한 것으로 나타났다. 식물의 무기음(無機陰)이온흡수에 미치는 양액중의 $NO_3-N$의 영향은 그 농도에 따라 다르며, $NO_3-N$농도가 낮을때는 주로 $Cl^-$과 그리고 $NO_3-N$농도가 높을때는 $SO_4{^{2-}}$ 및 $H_2PO_4{^-}$과 흡수길항관계(吸收拮抗關係)가 있었다.

• 한국토양비료학회지
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• 제48권1호
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• pp.30-35
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• 2015

This study was conducted to investigate investigated the effect of nitrogen fertilizer on nitrate concentration in soil solution and to determine the relationship between yield and nitrate concentration in soil solution for cucumber cultivation under plastic film house. Nitrogen as urea was applied at rates of 0, 120, 240, 360, and $480kg\;N\;ha^{-1}$ as an additional fertilizer by trickle irrigation during cucumber cultivation. Monitoring of nitrate concentration in soil solution was investigated using porous cups at 25 cm depth under soil surface. Nitrate concentration in soil solution increased with increasing the rate of additional nitrogen. Correlation coefficient between EC value and nitrate concentration was positive in soil and soil solution (p<0.05). An additional nitrogen of about $300kg\;ha^{-1}$ was shown the highest yield of cucumber, and improved yield by 5% compared to N recommendation of $240kg\;N\;ha^{-1}$. The highest yield was determined at nitrate concentration of $82mg\;L^{-1}$ in soil solution by regression equation ($Y=74.2+0.73X+0.000504X^2$, $R^2=0.629^*$). These results means indicate that nitrate concentration in soil solution would be useful method to rapid determination for additional nitrogen during cucumber cultivation under plastic film house.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.450-452
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• 2004

Using factor analysis and bivariate comparisons of major components in ground water, three geochemical processes were identified as controlling factors of ground water chemistry; 1) natural mineralization by water rock interactions, 2) effect of seawater which includes salinization by seawater near seashores and deposition of sea salt, and 3) nitrate contamination by N fertilization. Contribution of rainfall was also estimated from the measured composition of wet deposition. The geochemical processes were separated using total alkalinity as an indicator for natural mineralization, Cl for effect of seawater, and nitrate for N fertilization. Relatively high correlation of major components with nitrate suggests that nitrification of nitrogenous fertilizers significantly affects ground water chemistry. Total cations derived from nitrate sources have good linearity for nitrate in equivalent basis with a slope of 1.8, which is a mean of proton production coefficients in nitrification of two major compounds in nitrogenous fertilizers, ammonium and urea. Contribution of nitrate sources to base cations, Cl, and SO$_4$ in ground water was determined considering maximum contribution of natural mineralization to estimate a threshold of the effect of N fertilization for ground water chemistry, which shows W fertilization has a greatest effect than any other processes in ground water with nitrate concentration greater than 50 mg/L for Ca, Mg, Na and with concentration greater than 30 mg/L for Cl and SO$_4$.

• KSBB Journal
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• 제19권2호
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• pp.154-158
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• 2004

본 논문에서는 회분식 반응기에서 초기 산화환원전위가 ＋40 mV에서 -70 mV으로 낮아짐에 따라 탈질 속도는 1.25 mg/min에서 3.33 mg/min으로 증가하였고, 또한 회분식 반응기에서 질산성질소의 농도가 200 mg/1까지 증가할수록 nitrite의 축적없이 탈질 속도가 초기 농도에 비례적으로 증가하였다. 반면, 질산성질소의 농도가 400 mg/1가 되면 탈질 속도의 변화는 없으나 nitrite의 축적이 발생하기 시작하였으며, 질산성질소의 농도가 1,000 mg/l로 증가할 경우에는 많은 양의 nitrite가 축적이 되어 탈질의 저해가 발생하여 탈질 속도가 감소하였다. 회분식 반응기의 결과를 바탕으로, 충전탑식 반응기에서 유입수의 초기 산화환원전위를 낮추기 위하여 유출수를 재순환시킨 결과, 유입수의 초기 산화화원전위를 150 mV에서 30 mV로 낮출 수 있었고, 유입수의 초기 질산성질소의 농도를 120 mg/l에서 85 mg/l까지 낮출 수 있었다. 그 결과 충전탑식 반응기에서 유출되는 질산성질소의 농도가 재순환을 하기 전에는 약 61 mg/l이었으나, 유출수의 재순환으로 질산성질소의 농도를 10 mg/l까지 낮출 수 있었고, 질산 성질소의 제거율을 49.2%에서 91.7%로 증가시킬 수 있었다.