• Journal of Plant Biology
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• 제24권1호
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• pp.1-12
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• 1981

옥수수개체군의 생장기간중 생산구조의 발달과 건물생산과정에 따른 인의 동태, 즉 토양으로부터 흡수준, 동화율, 회전율, 수요공급의 수지 및 이용효율의 계절적 변화를 분석하였다. 인의 흡수율(최대 2.4mgPg$^{-1}$day$^{-1}$) 및 흡수효율(0.03)은 개체군의 상대생장률과 밀접한 상관을 보였고, 생육기간중 총 동화율은 3.41gPm$^{-2}$ 로서 월 최대 동화율은 2.99mgPg$^{-2}$ month$^{-1}$ (7월)였다. 한편 개체군의 인현존량의 변화는 최대치 1.4mgPg$^{-2}$ 였고, 최대 회전율은 178%를 나타내었다. 생육기간중 개체군의 각 기관별 인의 수요량은 엽 24.4%, 경 22.5%, 근 3.5% 및 종실 49.6% 였으며, 총 인요구량의 81.8%는 토양으로부터 흡수되였고 나머지 18.2%는 개체군내의 전류에 의해 공급되였다. 옥수수개체군의 인이용지수는 최대치가 6월에 1,091이며 평균지수는 655였다.

• 한국환경보건학회지
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• 제8권1호
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• pp.55-60
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• 1982

This study was carried out in order to clarify the combined effect of cadmium and lead on rat bones when exposed to single metal (1 mg cd/kg body weight) and cambined metals (1 mg cd + 4 mg pb/kg body weight). Seventy five mature rats of Sprague-Dawley species were divided into a control group and a treatment group that were administered by daily peritoneum injection for 7 to 9 weeds, and their body weights were measured every week. The results were summarized as follows 1. Body weight gains of the combined injection group and the single injection groups were lower than that of the control group. 2. In case of the combined injection group, the amount of cadmium accumulated in femur was more than that of the cadmium group. These amounts of cadmium accumulated showed an increasing trend. 3. The lead amount in bone tissue of the combined injection group presented also an increasing trend. In this case, the additive action of cadmium to the lead accumulation in bone tissue was conspicuous. 4. The amounts of calcium and phosphorus in femur showed clear a decreasing trend in the cadmium group and combined administration group. The ratio of calcium and phosphorus (ca/p) in the cadmium group was not different from that of the control group, but in the combined injection group the ratio was a little lower.

• 물과 미래
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• 제22권1호
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• pp.117-125
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• 1989

본 연구는 활성슬러지공법을 변형시킨 무산소일염기일호기반응조를 사용해서 질산화일탈질소반응 및 인의 방출인초과축적반응을 유도하여 합성페수의 유기물, 질소 및 인을 동시에 제거하였다. 무질소조, 무염기 및 호기호 각각에 대한 반응특성을 조사하기 위해 실험실규모의 반응조가 운영되었으며 MLSS농도를 5000, 4200, 3300, 2600, 1900mg/l로, 변화시켜 COD제거율에 대한 생물학적 동력학계수를 결정하였다. 연구결과, 유기물 및 영양염이 변형된 슬러지공법에 의해 동시에 제거될 수 있음을 알았고, ortho-p 제거효율은 66%∼99%로 높게 나타났다.

• 한국육종학회지
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• 제42권5호
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• pp.455-462
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• 2010

Purple acid phosphatase is important for phosphorus remobilization in plants, but its role in plant adaptation to low phosphorus availability is not known. The cDNA encoding O. sativa purple acid phosphatase (OsPAP1) has 1008 bp with an open reading frame of 335 amino acid residues. The amino acid sequence of OsPAP1 cDNA shows of 50-51% identity with other plant purple acid phosphatases. OsPAP1 was expressed in rice plants and in cell cultures in the absence of phosphate ($P_i$). The expression was organ-specific with the strongest expression in $P_i$-deprived roots. Functional expression of the OsPAP1 gene in the transgenic Arabidopsis line was confirmed by northern and western blot analysis. OsPAP1 overexpression lines had higher phosphatase activity than wild-type. Overexpression of OsPAP1 in Arabidopsis plants resulted in increased Pi accumulation under Pi sufficient condition. These results show that the OsPAP1 gene represents more efficient $P_i$ uptake and can be used to develop new transgenic dicotyledonous plants.

• 한국산림과학회지
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• 제97권5호
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• pp.492-500
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• 2008

Since vegetation significantly influences on soil carbon and nutrient storage, vegetation change has been focused on terrestrial carbon and nutrient cycling studies. In this study we investigated soil carbon and major nutrient capitals at the abandoned fields, which had different vegetation composition: a three year abandoned field ($AGR_3$), two ten years abandoned fields ($PD_{10}$ dominant with Pinus densiflora and Fraxinus rhynchophylla and $PM_{10}$ dominant with Populus maximowiczii), and an over sixty years forest ($FOR_{60}$). which were located at Hongcheon-gun, Kangwon-do, South Korea. Both main effects for organic matter (%) were significant: shallow soil > deep soil and $FOR_{60}=PM_{10}$ > $AGR_3=PD_{10}$. Nitrogen concentrations at $PM_{10}$ were the highest, while the lowest at $PD_{10}$. Available phosphorus concentrations were the highest at $PD_{10}$, which were over 10 times of site $FOR_{60}$ and $AGR_3$ at 0-10 cm soil depth. The average organic matter ($173Mg\;ha^{-1}$) and nitrogen contents ($10Mg\;ha^{-1}$) of $PM_{10}$ and $FOR_{60}$ were higher than those of $AGR_3$ and $PD_{10}$ by 57% and 42%, respectively. The available phosphorus contents above 30 cm mineral soil at $PD_{10}$ ($3.8Mg\;ha^{-1}$) and $PM_{10}$ ($1.3Mg\;ha^{-1}$) were over 120 times and 40 times more than at $FOR_{60}$. Calcium ($3.7Mg\;ha^{-1}$) and magnesium contents ($2.8Mg\;ha^{-1}$) at $FOR_{60}$ were twice or three times higher than at other sites. Organic matter amounts in 0-10 cm and 10-30 em soil had significant positive relationships with nitrogen, calcium, and magnesium contents, but not available phosphorus and potassium contents. This study could not identify the effect of chronological factor and vegetation composition on soil carbon and nutrient capital owing to diverse topography as well as limited study sites. However, this study suggests the accuracy of investigation for regional carbon and nutrient sequestration can be achieved by considering the period of abandoned time on the fields and the land use types. These results may suggest the benefits of forest restoration for soil carbon and nutrient accumulation in marginal agricultural lands in South Korea.

• 한국물환경학회지
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• 제24권6호
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• pp.709-717
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• 2008

The field scale experiment which is constructed with four sets (0.88 ha for each set) of wetland (0.8 ha) and pond (0.08 ha) systems was performed to examine the effect of plant coverage on the constructed wetland performance and to recommend the optimum development and management of macrophyte communities. After six growing seasons of wetlands, plant coverage was about 100%. And the concentration of DO showed low value (1.0~5.4 mg/L). This is caused by a blighted plant consumed dissolved oxygen with decay in water column. As the result, water column went to be anaerobic conditions and T-N removal rate are 58~67%. Dead vegetation increased nitrogen removal during winter because it is a source of organic carbon which is an essential parameter in denitrification. However, wetland released phosphorus caused by a blighted plant and accumulation, the removal rate of phosphorus might be decreased. To rise of DO concentration, the three open-waters were constructed in cell 3 and 4. Cell 3 has two open-waters (width 10 m, depth 1.8 m) and cell 4 has one open-water (width 20 m, depth 1.8 m). As the result, DO concentration and treatment efficiency of nutrient and BOD were improved. In case that constructed wetland is operated for a long time, physical circulation structure such as open water help continuous circulation of aerobic and anaerobic conditions. Through the constructed open-water, treatment efficiency of phosphorus and nitrogen in wetland could be improved effectively.

• 한국작물학회지
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• 제46권4호
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• pp.272-278
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• 2001

To investigate of C and N metabolisms in response to phosphorus-deficient stress during regrowth of Italian ryegrass (Lolium multiflorum L.), C and N metabolites were analyzed at 0, 6, 12 and 24 days after defoliation. P-sufficient (control, +P) and P-absent (-P) nutrient solutions were applied from 7 days before defoliation, and continued for one cycle of 24 day-regrowth period. During 24 days of regrowth, dry matter of regrowing shoots and remaining tissues were not significantly different between +P and -P treatment. In remaining stubble, 70% to 91 % decline of the initial level (at day 0) in all C compounds occurred during the first 6 days of regrowth. Initial amounts of nitrate and amino acids in roots were significantly higher in the +P medium. Nitrate contents in stubble in the +P medium significantly decreased for the first 12 days and then rapidly recovered, while that of the -P medium continuously decreased until day 24. Amino acids in stubble in the P medium were continuously increased during the whole regrowth period. Soluble proteins in stubble in the +P medium also largely fell down (46.0% of the initial) for only the first 6 days, however the decline in the -P medium continued until day 12. In regrowing shoots, the accumulation of C compounds was significantly higher, while that of N compounds except amino acids was largely lower in the -P medium. These results showed a stimulation of carbohydrate synthesis and a compensatory utilization of organic reserves occurred to support regrowth under P-deficient condition.

• 한국초지조사료학회지
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• 제13권1호
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• pp.23-30
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• 1993

인의 식물체로 부터 토양으로의 주요 환원경로인 litter의 분해과정에 관해서 조사하였다. 즉 생활형이 다른 Miscanthus sinensis. SaSa palmalta, Artemisia princeps 및 Polygonim thunbergii 군락에 있어서 litter로서 공급되어지는 총 낙엽량과 litter 존재량으로부터 litter의 소실속도를 구하였고, 또한 군락하에 nylon mesh bag 중에 litter를 집어 넣은 litter bag 을 설치하여, 그 내용물중의 감소속도로 부터 소실속도를 구하여 비교 검토하였다. 그 결과를 요약하면 다음과 같다. 1. 최대 litter 양은 Miscanthus＞SaSa＞Artemisia＞Polygonum 의 순이었지만, 년간의 litter 공급량은 Artemisia＞Miscanthus＞Polygonum＞SaSa의 순으로 나타났다. 2. 식물체 인의 토양에의 환원속도는 Polygonum＞Artemisia＞Miscanthus＞SaSa의 순으로 나타났다. 3. litter bag 법으로 산출된 소실속도는 자연상태에서 얻은 결과보다 소실속도가 늦은 경향을 보였다. 4. litter의 질소함유율과 litter의 소실속도와의 사이에는 강한 부의 상관을 보였다.

• 한국토양비료학회지
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• 제49권3호
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• pp.265-270
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• 2016

Accumulated Phosphate can be released by ligand exchange reaction of organic acids. The objective of this study was to evaluate effects of the organic acids on the availability of phosphate and the growth of crop in phosphate and salts accumulated soil. Soil samples were collected from farmer's plastic film house. Available phosphate and electrical conductivity of soil were $3,005mg\;kg^{-1}$ and $16.63mg\;kg^{-1}$ which were 6 and 8 times higher than the optimum range of soil for crop growth, respectively. Corns were cultivated in pots for 2 months. Treatments were no treatment (control), phosphate fertilizer (P), citric acid (CA) 1, 5, 10 mM, and oxalic acid (OA) 1, 5, 10 mM. Water soluble phosphorus, available phosphate, corn growth and uptake were determined after cultivation. Results showed that organic acids increased water soluble phosphorus and available phosphate. For the level of 10 mM, the order of effectiveness of organic acids for water soluble P was citric acid (44%) > oxalic acid (32%). Height and dry weight of corns were increased significantly by the treatment of citric acid 1 and 5 mM. Also, corn absorbed more phosphorus, nitrogen, potassium, calcium and magnesium in the treatment of citric acid 1 mM than these of other treatments. Even though phosphate availability of soil was enhanced by addition of citric acid 10 mM, the growth of corns decreased because high concentration of citric acid caused salt damage by increasement of electrical conductivity. Thus, the citric acid of 1 mM has the potential to improve the availability of phosphate and the healthy growth of corns.

• 한국미생물·생명공학회지
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• 제32권2호
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• pp.123-127
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• 2004

토양으로부터 oleic acid 를 탄소원으로 이용하여 MCL-PHA의 생산능이 우수한 균주를 분리하여 Pseudomonas sp. MBEL21이라 명명하였다. Pseudomonas sp. MBEL21의 PHA함량을 증가시키기 위하여 여러 가지 필수 영양분의 제한 조건에서 배양한 결과, 인산이 제한된 조건에서 가장 높은 함량의 PHA를 축적하였다. 고농도의 MCL-PHA생산을 위한 Pseudomonas sp. MBEL21의 유가식 배양 전략을 개발하여 28.1 wt％의 함량으로 23 g/L. MCL-PHA를 생산하였다. 또한, 분리된 Pseudomonas sp. MBEL21을 olive oil을 탄소원으로 이용하여 배양한 결과 9.3 wt％의 PHA가 축적되어졌으며, MCL-hydroxyalkanoate와 함께 3-hyoxy-butyrate 의 단량체들로 이루어진 PHA가 확인되어졌다. 이러한 결과들은 분리된 신규 Pseudomonas sp. MBEL21이 저가의 olive oil로부터 생분해성 탄성체의 응용분야를 갖는 MCL-PHA를 효율적으로 생산할 수 있다는 것을 보여준다.