• 한국토양비료학회지
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• 제38권4호
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• pp.211-217
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• 2005

미사식양토에서 질소로 $240kg\;ha^{-1}$에 상당하는 생헤어리뱃치와 화학비료 초안(질산암모늄)을 옥수수 파종 1주일 전에 토양에 혼입하고 옥수수를 재배하면서 토양 무기태질소, 미생물태질소, 옥수수 지상부의 질소 집적량을 1997년부터 2년간 조사하였다. 헤어리벳치의 초기분해 시 초안 유래의 질산태질소의 60-70%에 달하는 질소량이 헤어리뱃치로부터 무기화되어 토층 0-15 cm에 집적되었다. 또한 토양미생물태 질소도 헤어리뱃치구가 초안구보다 $10-20mg\;kg^{-1}$ 증가하였으며 약간의 헤어리뱃치 유래 토양무기태 질소는 천천히 무기화되어 출사기 이후까지 옥수수에 공급되는 것으로 보였다. 출사기에서의 옥수수의 전체 질소 집적량은 2년간 모두 두 질소원 간에 차이가 없었다. 옥수수 수확기의 질소 집적량은 1997년도에는 헤어리뱃치 녹비구가 초안구보다 8% 적었지만 1998년도는 오히려 19% 증가하였다. 질소원으로서 $240kg\;N\;ha^{-1}$에 달하는 헤어리벳치녹비의 시용은 완효적인 질소무기화 효과를 나타내었으며 같은 량의 질소 화학비료를 대체할 수 있는 옥수수 생육촉진 효과를 보였다.

• Journal of Ecology and Environment
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• 제31권3호
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• pp.167-176
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• 2008

Atmospheric N deposition has far-reaching impacts on forest ecosystems, including on-site impacts such as soil acidification, fertilization, and nutrient imbalances, and off-site environmental impacts such as nitrate leaching and nitrous oxide emission. Although chronic N deposition has been believed to lead to forest N saturation, recent evidence suggests that N retention capacity, particularly in the forest floor, can be surprisingly high even under high N deposition. This review aims to provide an overview of N retention processes in the forest floor and the implications of changing C-N interactions for C sequestration. The fate of available N in forest soils has been explained by the competitive balance between tree roots, soil heterotrophs, and nitrifiers. However, high rates of N retention have been observed in numerous N addition experiments without noticeable increases in tree growth and soil respiration. Alternative hypotheses have been proposed to explain the gap between the input and loss of N in N-enriched, C-limited systems, including abiotic immobilization and mycorrhizal assimilation, both of which do not require additional C sources to incorporate N in soil N pools. Different fates of N in the forest floor have different implications for C sequestration. N-induced tree growth can enhance C accumulation in tree biomass as observed across temperate regions. C loss from forests can amount to or outweigh C gain in N-saturated, declining forests, while another type of 'C-N decoupling' can have positive or neutral effects on soil C sequestration through hampered organic matter decomposition or abiotic N immobilization, respectively.

• 한국환경과학회지
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• 제13권3호
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• pp.245-250
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• 2004

The SBR(Sequencing Batch Reactor) process is ideally suited to treat high loading wastewater due to its high dilution rate. SBR operates by a cycle of periods consisting of filling, reacting, settling, decanting and idling. The react phases such as aeration or non-aeration, organic oxidation, nitrification, denitrification and other bio-logical reactions can be achieved in a reactor. Although the whole reactions can be achieved in a SBR with time distributing, it is hard to manage the SBR as a normal condition without recognizing a present state. The present state can be observed with nutrient sensors such as ${NH_{4}}^{+}-N$, ${NO_{2}}^{-}-N$, ${NO_{3}}^{-}-N} and ${PO_{4}}^{ 3-}-P.$ However, there is still a disadvantage to use the nutrient sensors because of their high expense and inconvenience to manage. Therefore, it is very useful to use common on-line sensors such as DO, ORP and pH, which are less expensive and more convient. Moreover, the present states and unexpected changes of SBR might be predicted by using of them. This study was conducted to get basic materials for making an inference of SBR process from ORP(oxidation reduction potential) of synthetic wastewater. The profiles of ORP, DO, and pH were under normal nitrification and denitrification were obtained to compare abnormal condition. And also, nitrite and nitrate accumulation were investigated during reaction of SBR. The bending point on ORP profile was not entirely in the low COD/NOx ratio condition. In this case, NOx was not entirely removed, and minimum ORP value was presented over -300mV. Under suitable COD/NOx ratio which complete denitrification was achieved, ORP bending point was observed and minimum ORP value was under -300m V. Under high COD/NOx ratio, ORP bending point was not detected at the first subcycle because of the fast denitrification and minimum ORP value was under -300mV at the time.

• 한국토양비료학회지
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• 제45권4호
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• pp.602-609
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• 2012

Burkholderia anthina R-4183, Burkholderia diffusa R-15930 and Burkholderia stabilis LMG 14294 isolated from green house soils (Gongju-Gun area, South Korea) were characterized and their phosphate solubilizing ability was assessed. Under in vitro culture conditions, all three species were proved to be effective in solubilizing phosphates in varying degrees. Strain Burkholderia anthina exhibited the highest phosphate solubilization in NBRIP medium ($665{\mu}g\;ml^{-1}$) followed by Burkholderia diffusa ($630{\mu}g\;ml^{-1}$) and Burkholderia stabilis ($578{\mu}g\;ml^{-1}$). However, solubilization of $FePO_4$ and $AlPO_4$ was found to be poor in all the strains. Acidification by means of gluconic and oxalic acids accumulation in the culture medium could be the possible mechanism responsible for phosphate solubilization. Glucose at the rate of 3% was found be the best carbon source for Burkholderia anthina while other two Burkholderia species showed maximum phosphate solubilization at 2% of glucose. In the case of nitrogen sources, ammonium and nitrate were equally effective in solubilizing phosphates by Burkholderia species. Despite a slight decrease in phosphate solubilization observed at increasing temperature, all three Burkholderia species could withstand a temperature of $30-35^{\circ}C$, pH at the range of 7-9 and the presence of NaCl (up to 2.5%) without much compromising the phosphate solubilization. As shown with potted mung bean seedlings, all the three isolates could enhance soil fertility and plant growth indicating their great potential to be used as bio-inoculants.

• 한국초지조사료학회지
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• 제17권3호
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• pp.223-230
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• 1997

The experiments were undertaken to investigate the dynamics of $NO_3\;^-$ uptake at low temperature with forage rape(Bmssica napus), barle(Hordeum vulgare) and winter rye (Scale cereale). A net $NO_3\;^-$uptake and the contents of nitrogenous compound in tissues at low temperature ($5^{\circ}C$) were compared with normal temperature ($25^{\circ}C$).The net uptake of $NO_3\;^-$ by Brass ica nqus was the highest among three species at both temperature applied. During 9 hours after temperature treatment, $NO_3\;^-$ uptake of Brassica napus, Hordeum vulgm and Scale c e d e grown at $5^{\circ}C$ decreased to about 31, 50 and 27% compared with those grown at $25^{\circ}C$. $NO_3\;^-$ contents in roots were much sensitively affected by low temperature than those of leaves. Comparing with the plants grown at $25^{\circ}C$, $NO_3\;^-$ contents in roots of increased to 48.3, 38.7 and 53.5% repectively, for Brassica napus, Hordeum vulgare and Scale cereale during 9 days. A relatively less changes in the content of $NH_4\;^+$-N were observed according to the temperature treatment. The ontents of amino acids-N in leaves at $5^{\circ}C$ slightly decreased while that of roods remarkably increased compared with $25^{\circ}C$. Protein-N was the largest pool of nitrogen and its contents in leaves and roots showed a similar response on the temperature treatment. These results suggested that $NO_3\;^-$uptake was inhibited at low temperature. The dynamics of $NO_3\;^-$ uptake could be closely related to the increased concentration of $NO_3\;^-$ and amino acids in roots.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.631-634
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• 2004

The method that exists in Photodynamic Therapy uses Photosensibility drug strongly Influencing tumour accumulation together with photochemical laser effect and makes the structure of tumour be localized and become extinct. The intracavity transformation of the Nd :YAP main radiation 1079 nm was Raman converted in barium nitrate crystal and the Stokes frequency (1216 nm) was doubled using KTP or RTA crystals. The LiF or Cr:YAG crystals are used for the Q-switch. The radiation Parameters were obtained at 100 Hz pump repetition frequency. The average power at 608 nm radiation with LiF and KTP was 700 mW at multi-mode generation. The 3-6 single 10-15 ns pulses were generated during one cycle of pumping. The doubling efficiency with RTA was two times more than with KTP. The cells of Ehrlich adenocarcinoma (0.1 ml) were i.m. implanted in hind thighs of ICR white non-imbred mice. The cells were preliminarily diluted in medium 199 in the ratio of 1 to 5. HpD was intravenous administered in a dose of 10 mg/kg. The left clean-shaven hind leg was irradiated with laser light 21-27 hours after the administration of the preparation. The right non-Irradiated leg of each animal served as a control. The animals with the transplanted tumor that were not injected with HpD sewed as a control to estimate the complex effect (HpD+ irradiation). Before the administration of HpD and on 3 and 4 days after irradiation the tumor size was measured and the percent of the tumor growth inhibition was calculated. The results of animal treatments has shown high efficiency of PDT method for cancer treatment by means 0.608 m high power pulse solid state laser.

• 한국환경농학회지
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• 제24권3호
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• pp.253-260
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• 2005

국내 시설하우스의 경우 화학비료를 비롯한 각종 농자재의 투입으로 인하여 비료 성분이 집적되었고 이는 작물의 수분흡수 장해를 유발하여 영양장해와 품질저하를 초래하고 있다. 또한 일부 지역에서는 농작물 가식 부위로의 ${NO_3}^-$ 축적과 질소 및 인의 용탈로 인한 수질 오염이 우려 된다. 본 연구에서는 연작장해가 발생한 시설채소재배지 토양의 물리화학적 특성을 평가하고 염류성분을 흡착 고정화할 수 있는 흡착제를 처리하여 토양용액에 존재하는 염류성분을 경감시킬수 있는 최적의 흡착제를 선별하고자 하였다. 실험에 사용된 토양은 유효인산$(1431{\sim}6516mg\;kg^{-1})$, 질산성 질소$(117.60{\sim}395.73mg\;kg^{-1})$, 치환성 칼슘$(4.06{\sim}11.07\;cmol_c\;kg^{-1})$ 및 마그네슘$(2.59{\sim}18.76\;cmol_c\;kg^{-1})$ 성분이 기준치를 과도하게 초과하여 염류장해를 유발하는 요인으로 작용하였다. 염류집적 토양에 대한 미강처리는 토양용액 내의 인산과 질산이온을 $93{\sim}100%$ 감소시켰으며 처리효율은 미강 > 혼합이온교환수지 > 분말형 제올라이트 순으로 나타났다. 미강을 제외한 모든 처리구는 pH $7.98{\sim}8.11$의 범위를 나타내었으며 미강 처리구에서는 토양의 pH가 6.61로 감소되었다. 미강 처리구의 경우 토양의 종류에 따른 차이는 있었으나 음이온에 대한 흡착능력이 매우 뛰어남을 알 수 있었다. 토양용액 중의 칼슘 이온에 대한 제거효율은 제올라이트 $1{\sim}65%$, 혼합이온교환수지 $7{\sim}61%$의 범위를 나타냈으며 미강의 경우 일부 토양에서는 토양용액 중의 칼슘 농도를 증가시키는 것으로 나타났으며 양이온교환수지의 경우 암모니움 이온과 칼륨 및 나트륨 이온에 대해서도 가장 뛰어난 흡착특성을 나타내었다. 이상의 결과를 통하여 양이온의 경우에는 혼합이온 교환수지 처리가 그리고 음이온의 경우 미강 처리가 토양용액 중의 염류성분의 흡착 제거에 뛰어난 효과가 있는 것으로 평가되었으며 경제적인 측면에서도 적용 가능할 것으로 판단되었다.

• 한국토양비료학회지
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• 제30권3호
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• pp.234-241
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• 1997

시설 재배지내 염류집적의 원인의 하나인 토양의 용적밀도 변화가 염류집적에 미치는 영향을 조사하기 위해, 충남 예산군 오가면의 시설재배 10여년 연작지 토양의 Ap층을 이용하여 용적밀도 변화에 따른 수리전도도 변화와 전기전도도 및 음이온의 용출특성 변화를 토주(土柱)실험을 통해 조사하였다. 수리전도도(Y, cm/day)와 용적별도(X, $Mg/m^3$)간에는 부의 회귀관계 ($Y=-19.2X^2+6X+15.5$, (r=0.985)) 가 성립하여, 낮은 용적밀도에서는 큰 폭의 수리전도도 감소가 있으며, $1.4Mg/m^3$ 이상의 높은 용적밀도 조건에서는 용적밀도 변화에 따른 수리전도도 변화가 매우 미미 하였다. 위의 5 수준의 용적밀도 조건하에서 시간변화에 따른 용출액 중 용존 물질의 용출속도는 용적밀도 증가에 따라 크게 지연되었다. 용출액의 전기전도도가 최고점에 도달하는 시간을 비교한결과 용적밀도 $1.3Mg/m^3$ 이하에서는 토양단면 10cm를 통과하는데 약 36시간 이내의 시간이 요구되었으며, 용적밀도 $1.4Mg/m^3$ 이상에는 120시간 이상이 요구되어 두 조건사이 약 84시간의 사이가 있었다. 토양내 이행성이 높은 주요 3가지 음이온의 용출속도도 용적밀도 증가에 따라 크게 지연되었으며, 용적밀도 $1.2Mg/m^3$ 일 때 Chloride, Nitrate와 Sulphate가 90%이상 용출 되는데 각각 17, 15, 35시간이 소요된 반면, 용적밀도 $1.5Mg/m^3$ 일 때 각각은 90%이상 용출 되는데 약 130, 125, 213시간이 각각 소요되었다. 따라서 경작층 전후의 큰 용적밀도 차이를 보이고 있는 충남 예산 지역의 시설재배지내 염류집적의 원인들 중 경작층 이하인 지표면 아래 20~30cm 부근에 형성된 용적밀도(容積密度) $1.5Mg/m^3$ 이상인 경반층(硬盤層)에 의한 토양수 흐름과 각종 무기염류의 이동 지연으로 인해 크게 악화되고, 지표면에 염류집적이 가속화된 것으로 판단된다.

• 한국초지조사료학회지
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• 제5권2호
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• pp.121-126
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• 1985

본(本) 시험(試驗)은 sorghum식물(植物)에 있어서 Cyanogenic glycosides의 합성(合成) 및 축적형태(蓄積形態)를 구명(究明)하기 위하여 sorghum hybrid의 Pioneer과 sorghum X sudangrass hybrid의 Sioux를 공시품종(供試品種)으로 하여 포장(圃場) 및 Phytotron시험(試驗)으로 실시(實施)하였다. Phytotron의 주(晝)/야간(夜間) 온도(溫度)는 30/25, 25/20, 28/18 및 $18/8^{\circ}C$로 하였으며 온도처리(溫度處理)는 출현기(出現期), 4 엽기(葉期), 6 엽기(葉期) 및 8 엽기(葉期)를 대상(對象)으로 실시(實施)하였다. 1979-'80년간(年間) 얻어진 시험결과(試驗結果)를 요약(要約)하면 다음과 같다. 1. HCN의 합성(合成) 및 축적(蓄積)은 출현(出現)과 동시(同時)에 이루어져 출현후(出現后) 5 - 7 일(日) 이 경과된 2 엽기식물(葉期植物)에서 각각(各各) Pioneer 931 2384ppm 및 Sioux 1798ppm으로 최고농도수준(最高濃度水準)에 달한다. 그러나 이들 함량(含量)은 생육(生育)이 진행(進行)됨에 따라 급격(急激)히 감소(減少)되어 출수기(出穗期)에는 각각(各各) 173ppm 및 70ppm으로 하락(下落)된다. 2. 생육기간중(生育期間中) HCN의 농도변화(濃度變化)는 LWR 및 LAR와는 정(正)(+)의 상관(相關)이 초장생육(草長生育)과는 부(負)(-)의 상관(相關)($P{\leqq}0.1%$)이 있다. 3 . 식물체중(植物體中) HCN 분포(分布)는 유수(幼穗)가 형성(形成)되기 이전(以前)의 유식물(幼植物)에서는 엽부위(葉部位)에 다량(多量) 분포(分布)되어 있으나 유수형성기(幼穗形成期) 이후(以后)에는 엽(葉)과 경부위간(莖部位間) HCN농도(濃度) 차이(差異)가 크지 않다. 4. Cyanogenic glycosides의 합성(合成)은 온도(溫度)가 상승(上昇)됨에 따라 비례적(比例的)으로 증가(增加)하나 식물체내(植物體內)의 HCN 축적(蓄積)은 고온(高溫)($30/25^{\circ}C$)에서 보다 저온(低溫)($18/8^{\circ}C$)에서 보다 크게 일어난다. 5. Cyanogenic glycosides의 합성(合成) 및 축적(蓄積)은 질소질비료(窒素質肥料) 및 NRA의 영향(影響)을 크게 받으므로 sorghum 식물체내(植物體內)에서의 HCN농도(濃度)는 $NO_3$축적(蓄積)과 높은 정(正)(+)의 상관(相關)이 있다.

• 한국토양비료학회지
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• 제47권6호
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• pp.563-570
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• 2014

The shortage or surplus of minerals directly affects overall physiological metabolism of plants; especially, it strongly influences carbohydrate metabolism as a primary response. We have studied mineral uptake, synthesis and partitioning of soluble carbohydrates, and the relationship between them in N, P or K-excessive tomato plants, and examined the interaction between soluble carbohydrates and mineral elements. Four-weeks-old tomato plants were grown in a hydroponic growth container adjusted with excessive N ($20.0mmol\;L^{-1}$ $Ca(NO_3)2{\cdot}4H_2O$ and $20.0mmol\;L^{-1}$ $KNO_3$), P ($2.0mmol\;L^{-1}$ $KH_2PO_4$), and K ($20.0mmol\;L^{-1}$ $KNO_3$), respectively, for 30 days. Shoot growth rates were significantly influenced by excessive N or K, but not by excessive P. The concentrations of water soluble N (nitrate and ammonium), P and K were clearly different with each tissue of tomato plants as well as the mineral conditions. The NPK accumulation in all treatments was as follows; fully expanded leaves (48%) > stem (19%) = roots (16%) = petioles (15%) > emerging leaves (1). K-excessive condition extremely contributed to a remarkable increase in the ratio, which ranged from 2.79 to 10.34, and particularly potassium was dominantly accumulated in petioles, stem and roots. Fresh weight-based soluble sugar concentration was the greatest in NPK-sufficient condition ($154.8mg\;g^{-1}$) and followed by K-excessive (141.6), N-excessive (129.2) and P-excessive (127.7); whereas starch was the highest in K-excessive ($167.0mg\;g^{-1}$) and followed by P-excessive (146.1), NPK-sufficient (138.2) and N-excessive (109.7). Soluble sugar showed positive correlation with dry weight-based total N content (p<0.01) whereas was negatively correlated with soluble P (p<0.01) and dry weight-based total P (p<0.01). On the other hand, starch production was negatively influenced by total N (p<0.001), but, it showed positive relation with total K concentration (p<0.05). This study shows that uptake pattern of NPK and production and partitioning of soluble carbohydrate were substantially different from each mineral, and the relationship between water soluble- and dry weight-based-mineral was positive.