• 아시안잔디학회지
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• 제7권1호
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• pp.31-34
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• 1993

There is a growing concern in the United Stares over the environmental and human health implications associated with heavy use of water, pesticides, and inorganic ferilizers in maintaining picture perfect golf courses. There is also a growing awareness that a beautiful course is not necessarily a healthy course. The following discussion reviews the interrelationship of turfgrass and the soil that supports it and provides basic information on currently available alternatives to turf management practices that feature intensive application of inorganic fertilizers. water and pesticides. Soil is a dynamic natural environment in which microorganisms play an important role. Soil contains a large mass of microorganisms which produce thousands of enzymes that can catalyze the transformation and degradation of many organic molecules. (In top soil under optimum conditions may contain 10 billion cells per gram of soil.). Turfgrass and the soil which supports it are interdependent. The natural organic cycle as applied to turf and soil begins with healthy vigorous grass plants storing up the sun's energy in green plant tissues as chemical energy. Animals obtain energy by eating plants and when plants and animals die, their wastes are returned to the soil and provide "food" for soil microorganisms. In the next step of the organic cycle soil microorganisms break down complex plant tissues into more basic forms and make the nutrients available to grass roots. Finally, growing plants extract the available nutrients from the soil. By free operation of this organic cycle, natural grasslands have some of the most fertile soils on earths.

• 환경영향평가
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• 제24권4호
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• pp.344-351
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• 2015

본 연구에서는 비소로 오염된 지역의 토양 및 지하수에 동전기적 기술을 사용하고 배양된 토양 미생물과 배양액을 주입하여 토양 내의 토착 미생물을 활성화하여 비소의 이동도를 상승시키는 것이 주요목표이다. 생물학적 동전기법은 미생물의 전기적 이동을 이용하여 기존의 생물학적 복원에서 문제시 되어온 늦은 분해속도와 낮은 제거효율의 단점을 극복할 수 있었다. 이는 전극의 전해액 대신 토양 미생물과 배양액을 혼합 주입하여 유기물질을 전자 공여체로 이용하는 다양한 토양 미생물이 Fe, Mn 등을 환원하게 된다. 이에 따라 주변의 금속 산화 미생물이 As(III)를 As(V)로 변환시킴으로써 As(III)의 이동도가 증가하게 되고, 이로 인해 As의 이동도가 기존 동전기법의 약 30%에 비해 60 ~ 70%정도로 상승함을 확인하였다.

• KSBB Journal
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• 제24권1호
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• pp.53-58
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• 2009

본 연구는 인위적으로 오염시킨 사질토와 미세토를 대상으로 미생물, 영양제 및 계면활성제를 이용하여 성능실험을 수행하여 시간에 따른 TPH와 BTEX의 제거 특성 등에 대해 알아보았다. 수분 함량을 10${\sim}$20%로 유지하면서 실험한 결과, 사질토를 이용한 TPH 제거율은 C군의 경우 C-1 (미생물+ 영양제), C-2 (미생물 + 영양제 + 계면활성제), C-0 (미생물) 순으로 높았고 경과시간 81 일에서는 각각 51%, 83%, 63%를 나타내었다. 미세토를 이용한 D군의 경우도 마찬가지의 양상을 보이고 있으나 C군 보다 더 낮은 TPH 제거율을 나타내었으며 미생물과 영양제를 투입한 경우가 가장 높았다. 미세토의 pH는 사질토의 pH 보다 다수 낮거나 유사한 수치를 나타내고 있고, C-0, C-1, C-2의 BTEX 제거율은 14일이 경과한 후 각각 99.8%, 99.4%, 96.0%이며 D-0, D-1, D-2의 제거율은 각각 99.5%, 99.2%, 96.3%로 미생물만 투입한 경우가 가장 높았다.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2001년도 10주년 기념 국제학술 심포지움 및 추계학술대회
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• pp.26-29
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• 2001

• Journal of Ginseng Research
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• 제21권2호
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• pp.91-97
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• 1997

In order to elucidate the mechanism of red-colored phenomena(RCP) in ginseng(Panax ginseng C.A. Meyer), distribution of inorganic elements of ginseng root and its surrounding soil, and microflora in the soil were investigated. Red brown colored-substances were accumulated in the cell wall of epidermis at early stage of red-colored ginseng (RCG). Cell wall of the late stage of RCG was disordered and microorganisms were shown in the disordered cell wall. Al, Si and Fe contents among inorpanic elements in the epidermis of RCG were higher at two or three times than that of healthy ginseng. On the other hand, K content was higher at three times in healthy ginseng than that of RCG. Especially, Fe content was higher at three times in lateral roots of RCG than that of healthy ginseng. Total 21 strains of microorganisms were isolated on the 523 medium from surface soil, surrounding soil of both healthy and RCG, and RCG. Six strains of microorganisms among them were resistant to 2 mM Fe. Two species in Bacillus app. and Lactobacillus app. , and one species in Micrococcus sp. and Npisseria sp. respectively were identified. It seemed that RCP was closely related with the distribution and uptake of inorganic elements, was also correlated Fe-independent metabolism of microorganisms.

• 아시안잔디학회지
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• 제10권3호
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• pp.247-262
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• 1996

In this study, the distribution of dictyostelid cellular slime molds was investigated from F, H and $A_1$ horizon of pinus, oak forests in Mt. Puk'an, Mt. Nam and Mt. Kwanak. The relationship of cellular slime molds with other soil microorganisms and abiotic factors were analyzed. The six species were isolated as follows: Polysphondlium pallidurn, Dictyostelium purpureum, D. mucoroides, D. crassicaule, D. capitatum, D. implicatum. The dominant species in pinus forests was P. pallidum, and in oak forests it was D. macro ides. In Mt. Nam, D. mucoroides and P. pallidum were isolated at only oak forest. The Correlations of slime mold abundance with bacteria were significant. Even though positive correlations of cellular slime molds with actinomycetes or fungi were not significant, correlations between soil microorganisms were analyzed. Correlation coefficients were high in Mt. Kwanak(r=0.5921) and Mt. Nam(r=0.7243) at significant level P<0.01. There were significant correlations between total slime molds and abiotic factors. It supports that cellular slime molds are limited by foods in nature. In low level of pH, water content and organic matter, that community diversity is more affected by bacteria whose organic degradation capacity is regulated by interactions of soil microorgaisms. Key words: Cellular slime molds, Soil microorganisms, Correlations, Abiotic factors.

• Environmental Engineering Research
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• 제7권2호
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• pp.67-73
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• 2002

• Journal of Microbiology and Biotechnology
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• 제26권7호
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• pp.1303-1310
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• 2016

Although many studies on the effects of genetically modified (GM) crops on soil microorganisms have been carried out over the past decades, they have provided contradictory information, even for the same GM crop, owing to the diversity of the soil environments in which they were conducted. This inconsistency in results suggests that the effects of GM crops on soil microorganisms should be considered from many aspects. In this study, we investigated the effects of the GM drought-tolerant rice MSRB2-Bar-8, which expresses the CaMSRB2 gene, on soil microorganisms based on the culture-dependent and culture-independent methods. To this end, rhizosphere soils of GM and non-GM (IM) rice were analyzed for soil chemistry, population densities of soil microorganisms, and microbial community structure (using pyrosequencing technology) at three growth stages (seedling, tillering, and maturity). There was no significant difference in the soil chemistry between GM and non-GM rice. The microbial densities of the GM soils were found to be within the range of those of the non-GM rice. In the pyrosequencing analyses, Proteobacteria and Chloroflexi were dominant at the seedling stage, while Chloroflexi showed dominance over Proteobacteria at the maturity stage in both the GM and non-GM soils. An UPGMA dendrogram showed that the soil microbial communities were clustered by growth stage. Taken together, the results from this study suggest that the effects of MSRB2-Bar-8 cultivation on soil microorganisms are not significant.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권2호
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• pp.16-24
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• 2014

To test the potential effects of extracellular electron shuttles (EES) on the rate and extent of heavy metal release from contaminated soils during microbial iron reduction, we created anaerobic batch systems with anthraquinone-2,6-disulfonate (AQDS) as a surrogate of EES, and with contaminated soils as mixed iron (hydr)oxides and microbial sources. Two types of soils were tested: Zn-contaminated soil A and As/Pb-contaminated soil B. In soil A, the rate of iron reduction was fastest in the presence of AQDS and > 3500 mg/L of total Fe(II) was produced within 2 d. This suggests that indigenous microorganisms can utilize AQDS as EES to stimulate iron reduction. In the incubations with soil B, the rate and extent of iron reduction did not increase in the presence of AQDS likely because of the low pH (< 5.5). In addition, less than 2000 mg/L of total Fe(II) was produced in soil B within 52 d suggesting that iron reduction by subsurface microorganisms in soil B was not as effective as that in soil A. Relatively high amount of As (~500 mg/L) was released to the aqueous phase during microbial iron reduction in soil B. The release of As might be due to the reduction of As-associated iron (hydr)oxides and/or direct enzymatic reduction of As(V) to As(III) by As-reducing microorganisms. However, given that Pb in liquid phase was < 0.3 mg/L for the entire experiment, the microbial reduction As(V) to As(III) by As-reducing microorganisms has most likely occurred in this system. This study suggests that heavy metal release from contaminated soils can be strongly controlled by subsurface microorganisms, soil pH, presence of EES, and/or nature of heavy metals.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.196-201
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• 2000

The influence of adsorption on cadmium toxicity to soil microorganisms in smectite-rich soils and sediments was quantified as a function of solution and sorbent characteristics. Adsorption and surface complexation experiments were conducted to infer Cd sorption mechanisms to a reference smectite and three fractions of a Veritsol soil, and to elucidate the effects of the surface complexation on Cd bioavailability and toxicity in soils and sediments. Cadmium adsorption isotherms conformed to the Langmuir adsorption model, with adsorptive capacities of the different samples dependent on their characteristics. Equilibrium geochemical modeling (MINTEQA2) was used to predict the speciation of Cd in the soil suspensions using Langmuir and Triple Layer surface complexation models. The influence of adsorption and surface complexation on cadmium toxicity to soil microorganisms was assessed indirectly through the relative change in microbial hydrolysis of fluorescein diacetate (FDA) as a function of total Cd concentration and sorbent characteristics. Adsorption decreased the toxicity of Cd to soil microorganisms. Inner-sphere complexation is more effective than outer-sphere complexation in reducing the bioavailability and toxicity of heavy metals in soils and sediments.