• Journal of Ecology and Environment
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• 제40권1호
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• pp.75-83
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• 2016

Background: In order to evaluate the effect of pH, known as a critical factor for shaping the biogeographical microbial patterns in the studies by others, on the bacterial diversity, we selected two sites in a similar geographical location (site 1; north latitude 35.3, longitude 127.8, site 2; north latitude 35.2, longitude 129.2) and compared their soil bacterial diversity between them. The mountain soil at site 1 (Jiri National Park) represented naturally acidic but almost pollution free (pH 5.2) and that at site 2 was neutral but exposed to the pollutants due to the suburban location of a big city (pH 7.7). Methods: Metagenomic DNAs from soil bacteria were extracted and amplified by PCR with 27F/518R primers and pyrosequenced using Roche 454 GS FLX Titanium. Results: Bacterial phyla retrieved from the soil at site 1 were more diverse than those at site 2, and their bacterial compositions were quite different: Almost half of the phyla at site 1 were Proteobacteria (49 %), and the remaining phyla were attributed to 10 other phyla. By contrast, in the soil at site 2, four main phyla (Actinobacteria, Bacteroidetes, Proteobacteria, and Cyanobacteria) composed 94 %; the remainder was attributed to two other phyla. Furthermore, when bacterial composition was examined on the order level, only two Burkholderiales and Rhizobiales were found at both sites. So depending on pH, the bacterial community in soil at site 1 differed from that at site 2, and although the acidic soil of site 1 represented a non-optimal pH for bacterial growth, the bacterial diversity, evenness, and richness at this site were higher than those found in the neutral pH soil at site 2. Conclusions: These results and the indices regarding diversity, richness, and evenness examined in this study indicate that pH alone might not play a main role for bacterial diversity in soil.

• The Korean Journal of Ecology
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• 제9권4호
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• pp.231-241
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• 1986

The annual decomposition of cellulose and hemicellulose by microorganism and distribution of soil microbial flora were investigated in the humus horizon of a Pinus rigida stand in Mt. Kwanak. The cellulase activity was the lowest, 142$\mu$g glucose/g/hr from Dec. 1985 to Mar. 1986 and the highest, 760~1, 072$\mu$g glucose/g/hr in Jul. and Aug. 1985. The xylanase activity was 47% higher than the cellulase activity and was the lowest, 211~275$\mu$g xylose /g/hr from Feb. to Mar. 1986 and the highest as 799~1, 322$\mu$g xylose/g/hr from Jun. to Aug. 1986. The vertical distribution of the enzyme activity was decreased with the order of F, H, L, and A1 in both enzymes and the activities were exponentially decreased below L horizon, which suggests that most decomposition be done in F and H horizons with lots of organic matters. The SEM study slowed that the main decomposers of litters were fungi and initial attack into litters was also made by them. The enzyme activities of soil had strong correlations with the temperature and the precipitation. The correlation coefficients were 0.813 and 0.886 in the cellulase, and 0.673 and 0.626 in the xylanase for the temperature and the precipitation, respectively.

• The Korean Journal of Ecology
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• 제21권5_2호
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• pp.575-583
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• 1998

Physicochemical factors, microbial population size and the properties of the bacterial isolates were assessed to find out the nature of soil ecosystem of Mt. Paektu. Samples were obtained from the surface layer of soils on which specific plant community is developed. Average content of moisture, organic matter and avaiable phosphate of the soils were 21.6%, 17.3% and 2.48mg/100g, respectively. These values were similar to those of developing forest soils, but were slightly lower than those of climax ecosystem such as Piagol in Mt. Chiri. The population size of soil bacteria ranged from 2.7 to $202.5{\times}10^5$ CFU/g.dry soil, and the size is somewhat dependent on the content of moisture and oranic matter of the forest soil. A large number of bacteria was able to decompose macromolecules such as starch, elastin and gelatin. While the distribution rate of resistant bacteria to antibiotics was high, that to toxic chemicals was low. This means that the competition between microorgani는 predominate over the interference with artificial behaviour such as spread of pesticides in the surveyed region. Bacterial species composition of each soil was comparatively simple. Pseudomonas, Agrobacterium, Flavobacterium and Xanthomonas which are Gram-negative short rods were widely distributed in the forest soils. The endospore forming Bacillus species were also main constituents of the soil microflroa. any one of the strains was not identified as Azospirillum or Micrococcus which are known to be one of major constituents of the forest soil. for the correct identification of isolates chemotaxonomic studies will be proceeded, and the strains are to be stored in the Type collection Center.

• 한국지하수토양환경학회지:지하수토양환경
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• 제14권3호
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• pp.57-67
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• 2009

토양미생물은 토양 및 퇴적토 환경에서 생물학적 물질순환의 중요한 역할을 맡고 있다. 이러한 중요성으로 인해 토양미생물 생태 다양성과 군집구성이 토양 및 퇴적토 생태환경과 자연저감능력을 평가하는 지표로 유용하게 쓰일 수 있다. 보다 정확한 다양성과 군집구조 분석을 위해서는 다양한 토양 및 퇴적토 시료로부터 분석에 필요한 DNA수율과 순도를 확보해야 한다. 지금까지 토양 및 퇴적토에서 DNA추출하는 방법들에 대한 다양한 기초연구가 이루어졌지만, 실제 환경생태영향평가와 분해기능평가에 사용시 DNA추출방법 선정에 대한 지침 및 정보는 매우 부족하다. 이에 본 연구에서는 문헌조사를 통해서 다양한 방법들의 토양 및 퇴적토 내 미생물 DNA 추출 특성을 비교 분석하고, 현재 주로 사용되고 있는 DNA추출방법을 토양 및 퇴적토 환경평가나 오염지하수토양 자연저감능평가에 활용 할 경우 고려해야 할 기술적 사항에 대해 고찰하였다. 본 연구를 통해 하나의 특정 추출 방법으로는 미생물다양성, 군집구성 및 개체간 상호작용에 대한 정보를 얻기에는DNA양과 순도 차원에서 충분하지 않으며, 토양 및 퇴적토 미생물 군집분석의 목적에 따라 적합한 방법의 선택이 매우 중요함을 알 수 있었다.

• The Korean Journal of Ecology
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• 제21권5_3호
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• pp.703-712
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• 1998

Physicochemical factors, microbial population size and the properties of the bacterial isolates were estimated to find out the nature of soil ecosystem of Mt. Nam. Samples were obtained from the surface layer of soils on which specific plant community is developed. Average content of moisture and organic matter of the soils were 21.6% and 17.3%, respectively. These values were similar to those of developing forest soils, but were slightly lower than those of climax ecosystem such as Piagol in Mt. Chiri. Chiri. Content of phosphate was higher than those of other forest soils. The population size of soil bacteria ranged from 27.4 to 195.8 ${\times}\;10^5$ CFU/g. duy soil, and the size is somewhat dependent on the moisture and oranic matter content of soils. A large number of bacteria were able to decompose macromolecules such as starch, elastin and gelatin. Bacterial species composition of each soil was comparatively simple. Pseudomonas, Agrobacterium, Flavobacterium and Xanthomonas which are Gram-negative short rods were widely distributed in the forest soils. The endospore forming Bacillus species were also the main constituents of the soil microflroa. Actinomycetes were widely distributed in the forest soils, but the distribution pattern varied in each site. Most of the actinomycetes were also able to decompose organic macromolecules. The rate of resistant actinomycete strains to antibiotics and heavy metals were lower than those from cultivated soils, but higher than those from well-preserved forest soils. Antibiosis pattern of the actinomycete isolates was similiar to the resistance pattern. This means the forest soils of Mt. nam was somewhat interferred by artificial behabiour.

• 한국토양비료학회지
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• 제48권4호
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• pp.285-294
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• 2015

Ordination has been recognized useful method to analyze the effects of multiple environmental factors on dozens of species in vegetation ecology because of summarizing community data by producing a low-dimensional graphics. Main objective of this study was the application of ordination method, especially principal components analysis (PCA), to analyze the soil characterization on paddy treated by different green manure crops and tillage methods. Treatments included the three tillage treatments and two green manure crops as the following; (i) moldrotary + rotary tillage without green manure crop (Con), with (ii) hairy vetch (ConHv), and (iii) hairy vetch + green barely (ConHvGb), (iv) rotary tillage without green manure crop (Rot), with (v) hairy vetch (RotHv), and (vi) hairy vetch + green barly (RotHvGb), and (vii) no-tillage (Notill). Vectorial distance result from PCA of soil properties including physical, chemical, and microbial properties showed the two main difference. Firstly, soil properties among plots without green manure were strongly affected by tillage strength [Vectorial distance: Con-Notil (5.88) > Rot-Notill (4.58)] at PC1 (35.0%) axis. But it was difficult to find the fixed trend among plots when green manure crop was added in plot. Nevertheless, two groups were separated by adding green manure crop at PC2 (29.2%) axis. These results show that PCA ordination methods could be used the research for change of soil characterization.

• 미생물학회지
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• 제44권1호
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• pp.63-68
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• 2008

참외 경작지 토양으로부터 순수 분리된 선충포식성 곰팡이 Kan-23 균주는 배양 30일 이후에 분생포자가 형성되는 증식이 매우 더딘 특성을 나타내었다. 주사전자현미경(SEM)을 이용하여 Kan-23 균주의 미세형태 구조를 관찰한 결과 분생포자병의 각 가지마다 $5{\sim}10$개의 분생포자를 형성하였으며, 분생포자는 3개의 격막을 형성하고 타원형을 나타내었고, 수축성 고리형태(constricting ring)의 포식 구조체를 형성하는 특징을 나타내었다. 다양한 배지를 이용하여 포식 구조체의 형태학적 특성을 비교 검토한 결과 GPA 배지에서 2배 이상 크기의 대형 수축성 고리 형태의 포식 구조체를 형성하는 특징을 나타내었다. Kan-23 균주의 rDNA의 ITS 영역의 염기서열을 분석한 결과, Drechslerella 속의 계통군에 속하였으며, 특히 Drechslerella brochopaga (U51950)와 99%의 높은 염기서열 유사도를 나타내어 Drechslerella brochopaga로 동정되어 국내 미기록종임이 확인되었다.

• Applied Biological Chemistry
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• 제50권2호
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• pp.101-106
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• 2007

국내 다양한 토양시료로부터 우수 선충포식곰팡이 9 균주를 선발하였다. 순수분리된 선충포식곰팡이는 포식기관의 형태에 따라 3차원적 점착성 그물구조(3-dimensional adhesive nets)를 나타내는 선충포식곰팡이(A 그룹), 2차원적 점착성 그물구조(2-dimensional adhesive nets)를 나타내는 선충포식곰팡이(B 그룹)와 수축성 고리구조(constricting ring)를 나타내는 선충포식곰팡이(C 그룹)로 크게 3개의 형태그룹으로 분류되었다. 이들 각 그룹에 속하는 선충포식곰팡이의 균사체, 분생포자병, 분생포자의 모양과 크기, 분생포자 형성 개수, 분생포자 마디(node), 분생포자 격막의 수와 격막의 위치, 휴면포자의 형성과 크기 및 색 등 형태학적 특징과 선충포식곰팡이의 rDNA ITS 영역을 PCR로 증폭하여 염기서열을 분석한 결과, 분리된 포식곰팡이는 Monacrosporium thaumasium(Kan-2, Kan-4, Kan-11), Arthrobotrys oligospora(Kan-9, Kan-13, Kan-20, Kan-21), A. musiformis (Kan-12), A. dactyloides(Kan-22)로 동정되었다.

• 미생물학회지
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• 제44권1호
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• pp.56-62
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• 2008

송이 자실체 기저부 토양으로부터 분리한 268균주를 대상으로 식물병원성 곰팡이 7균주(Alternaria panax, Botrytis cinerea, Colletotrichum gloeosprioides, Fusarium oxysporum, Phytopthora capsici, Pythium ultimum, Rizoctonia solani)에 대해 항균활성을 검토한 결과 인삼점무늬병원균(Alternaria panax)과 인삼탄저병원균(Colletotrichum gloeosprioides)에 강한 항균활성을 나타내는 KM1-15 균주가 선발되었다. KM1-15 균주의 16S rDNA 염기서열(1,311 bp)을 결정하여 계통학적 위치를 검토한 결과, Bacillus $koguryoae^T$ (AY904033)와 99.6%의 상동성을 나타내었다. API 50CHE Kit를 사용하여 당 분해능에 대해 Bacillus $koguryoae^T$ (AY904033)와 비교 검토한 결과 KM1-15 균주는 L-arabinose, cellobiose, inulin, D-turanose 양성반응을 나타내는 생리학적 특성이 확인되었다. 주요 지방산으로는 15:0 anteiso (35.78%), 17:0 anteiso (17.97%)를 함유하였으며, 13:0 iso 3-OH, 14:0 iso3-OH, 15:0 iso 3-OH, 그리고 17:0 iso 3-OH와 같은 다양한 분지형 지방산을 함유하는 특성을 나타내었다. 퀴논종으로는 MK-7 (100%)을 가지고, G+C함량은 43.7%를 나타내었다. 또한 protein과 starch에 대한 가수분해능이 탁월하여 KM1-15 균주는 병해충 방제제 및 토양개량제로 매우 유용하게 활용될 것으로 사료된다.

• 한국산림과학회지
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• 제100권4호
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• pp.681-686
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• 2011

본 연구 목적은 광릉시험림 지역의 침엽수림과 활엽수림에서 토양 깊이가 미생물상과 중형동물상 분포에 미치는 영향을 구명하는 것이다. 토양 미생물상은 인지질지방산(PLFA) 지표를 이용하여 그 밀도정도를 분석하였고, 중형동물상은 선충과 미소절지동물의 밀도를 조사하였다. 미생물 PLFA지표는 B층보다 A층에서 높았고, 산림형에 따른 차이는 적었다. 선충 밀도도 A층에서 높았으며, 곰팡이섭식성 선충의 밀도는 침염수림 토양보다 활엽수림 토양에서 높게 나타났다. 미소절지동물 중에서 톡토기와 날개응애의 평균밀도는 전체 미소절지동물 밀도의 44%와 42%를 각각 보였다. 세균과 곰팡이를 나타내는 PLFA 지표가 이들을 섭식하는 중형동물과 유의한 양의 상관관계가 있었으며, 이것은 이 지역 토양에서 세균과 곰팡이를 중심으로 한 먹이망 형성이 이들의 분포에 영향을 준다는 것을 나타낸다. 이러한 결과는 광릉시험림의 토양생물 분포는 주로 토양의 깊이에 영향을 받으며, 산림형은 부분적인 영향을 주고 있음을 알 수 있었다.