• 한국토양비료학회지
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• 제48권2호
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• pp.132-137
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• 2015

Effects of chitin and chitosan treatments on soil microorganisms and the mesofauna were investigated in a microcosm and a fumigated field experiment. Responses of microorganisms were determined using microbial phospholipid fatty acid (PLFA) analysis, whereas responses of the mesofauna were measured in terms of the abundances of nematodes and microarthropods. Soil nitrate concentration increased on the application of chitin. Overall, chitin promoted bacterial and fungal abundance, leading to an increase in abundance of free-living soil nematodes that feed on decomposers. The ratio of saturated to unsaturated fatty acids was highest in the chitin-treated soil. Chitosan had a minimal effect on the abundance of microorganisms; however, it reduced the abundance of collembolans in the microcosm experiment. These results indicate that the application of chitin has beneficial effects on the supply of nutrients and promotion of the abundance of soil organisms.

• 환경생물
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• 제22권3호
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• pp.400-404
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• 2004

유기합성적으로 제조된 지방족 폴리에스테르의 일종인 polycaprolactone (PCL)을 $27^\circ{C}$와 $37^\circ{C}$로 온도를 달리한 활성오니토양에 66일간 매립하여 토양미생물에 의해 분해된 PCL 필름의 표면변화를 관찰하고, PCL을 분해하는 토양진균과 토양세균을 분리, 동정하였다. PCL을 탄소원과 에너지원으로 이용하는 토양진균으로는 Paecilomyces fumosoroseus KH27, Penicillium digitatum KH28, Fusarium solani KH29와 Aspergillus sp. KH30, 토양세균으로는 Ochrobactrum anthropi KH3l이 분리되었다. $27^\circ{C}$에서는 P. digitatum KH28이 가장 높은 PCL 분해능(46%)을 보였고, $37^\circ{C}$에서는 O. anthropi KH31의 분해능(52%)이 가장 우수하였다.

• 한국지반환경공학회 논문집
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• 제10권7호
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• pp.93-101
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• 2009

스탠딩 컬럼웰(Standing Column Well) 히트펌프시스템은 지하수의 열교환으로부터 지열에너지를 생산한다. 모의지열펌프시스템(SHPS)을 제작하고 이를 이용하여 변화하는 토양의 온도를 관찰하고, bleeding 실험 후 SHPS 내에서 토양 미생물의 양과 종의 변화를 파악하였다. 이와 같은 실험을 통해 토양의 온도 변화와 수분의 변화에 의해 토양 내 미생물의 전반적인 양은 감소하였고, 종의 개체수가 감소함을 볼 수 있었다. 열원으로 사용되는 지하수의 성상분석을 통해 사용 전 후의 특성을 파악하고, 지하수 시료를 생활용수 기준으로 수질 분석 하였다. 그 결과 지하수의 수질 자체가 매우 양호하여 지하수 오염은 일어나지 않은 것으로 파악되었다. 또한 지하수 시료의 경우에도 지하수 내 존재하고 있는 미생물의 종과 양의 변화를 파악하여, 열원으로 사용 전 후의 미생물의 종과 양이 변화 한다는 것을 알 수 있었다. 지하수의 온도가 2-3도 증가함에 따라 미생물의 양이 90% 정도 늘어났으며, 토양에 비해 종의 변화는 크지 않음을 확인할 수 있었다.

• 한국환경농학회지
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• 제15권1호
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• pp.105-115
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• 1996

In this paper, we reviewed the degradation factors of diazinon which was known to be easily degraded by soil microorganisms and lost of its activity. Under submerged soil condition, the contribution of microorganisms to diazinon degradation was about 40% and these microorganisms preferred soil humus as substrates to diazinon itself. The effect of monooxygenase activity in submerged soil was more important than esterase activity on diazinon degradation and these enzymes were inhibited by several chemicals such as piperonyl butoxide(PBO), EPN and tricyclazole. From these results, new formulation type of diazinon (PBO and triphenyl phosphate were added to commercial diazinon formulation by 0.1% respectively.) and diazinon mixture formulation (diazinon was mixed with EPN, tricyclazole and carbofuran in equal amount) were prepared. The new formulation type of diazinon showed better insecticidal activity by 12% and more delayed diazinon degradation in ten days than commercial diazinon.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.158-161
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• 2004

Chlorinated aliphatic hydrocarbons (CAHs) especially perchlorethylene (PCE) and trichlooethylene (TCE) are common groundwater contaminants in Korea. PCE and TCE were often reductively dechiorinated in an aquifer. Several isolates dechlorinate PCE to TCE or cis-1,2 dichloroethylene (c-DCE) were obtained from contaminated and pristine sites in USA and Europe. However in Korea, no information on indigenous microorganism being involved in reductive dechlorination of PCE and TCE is available and different dechlorinating microorganisms might be reside in Korea, since geochemical, and hydrogeological conditions are different, compared to those in the other sites. So we evaluate that: 1) if reductive dechlorinating microorganisms are present in PCE-contaminated site in Korea, 2) if so, what kinds of microorganisms are present; 3) to what extent PCE is reductively dechlorinated. As a results in some PCE-contaminated aquifers in Korea other dechlorinating microorganisms but Dehalococcoides ethenogenes may be responsible for PCE dechlorination. More detailed molecular works are required to evaluate that different dechlorinating microorganisms would reside in Korea.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권3호
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• pp.88-94
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• 2016

The simultaneous biodegradation between MTBE (Gasoline additives) and BTEX (Benzene, Toluene, Ethyl-benzene, o-Xylene, m-Xylene, p-Xylene) was achieved within a competitive inter-relationship, with not only electron accepters such as nitrate, sulfate, and iron(III) without oxygen, but also with electron donors such as MTBE and BTEX. Preexisting indigenous microorganisms from a domestic sample of gasoline contaminated soil was used for a lab-scale batch test. The result of the test showed that the biodegradation rate of MTBE decreased when there was co-existing MTBE and BTEX, compared to having just MTBE present. The growth of indigenous microorganisms was not affected in the case of the MTBE treatment, whereas the growth of the microorganisms was decreased in combined MTBE and BTEX sample. This may indicate that an inhibitor related to biodegradation when BTEX and MTBE are mixed will be found. This inhibitor may be found to retard the anaerobic conditions needed for efficient breakdown of these complex carbon chain molecules in-situ. Moreover, it is also possible that an unknown competitive reaction is being imposed on the interactions between MTBE and BTEX dependent on conditions, ratios of mixture, etc.

• Journal of Microbiology and Biotechnology
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• 제20권6호
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• pp.1027-1031
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• 2010

To examine the possibility of horizontal gene transfer between transgenic potatoes and microorganisms in potato fields, the gene flow from transgenic potatoes containing the nucleoside diphosphate kinase 2 (NDPK2) gene to microorganisms in soils was investigated. The soil samples collected from the potato fields from March to October 2007 were examined by PCR, Southern hybridization, and AFLP fingerprinting. The NDPK2 gene from soil genomic DNAs was not detected by both PCR and Southern hybridization, indicating that gene transfer did not occur in the potato fields. In addition, no discrepancy was found in pathogenicity and noticeable changes for the appearance of variants of Phytophthora infestans in each generation when serial inoculations and the analysis of genomic DNAs by AFLP were conducted. Thus, these data suggest that transgenic potatoes do not give significant impacts on the communities of soil microorganisms and the emergence of variants, although continued research efforts may be necessary to make a decisive conclusion.

• 대한환경공학회지
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• 제22권10호
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• pp.1757-1763
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• 2000

본 연구는 토양미생물을 활성화한 영양염류 제거 공정의 질소, 인 제거 특성을 Denitrifying Phosphorus removing Bacteria(DPB)의 영향에 의한 관점에서 파악하고자 행하였으며, 또한 DPB의 무산소 상태 하에서의 탈질 및 인 섭취 특성에 대해서도 연구가 진행되었다. Batch test 결과, 토양미생물을 이용한 영양염류 제거 공정에서의 질소, 인 제거는 무산소 상태에서 탈질과 동시에 인을 섭취하는 DPB(Denitrifying Phosphorus removing Bacteria)의 영향이 상당한 것으로 나타났으며 무산소 상태에서의 DPB에 의한 인 섭취 속도가 호기상태에서의 약 50%에 달하였고 초기 nitrate 농도가 DPB의 인 섭취 속도에 대한 영향인자임을 알 수 있었다. 그리고 영양염류 제거 공정에서의 DPB의 존재는 전체 공정의 효율을 증대시키는 것으로 판단되었다.

• 한국환경복원기술학회지
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• 제18권4호
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• pp.63-71
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• 2015

Recently the roof gardening has become very popular and even on the apartment-veranda and on the roofs in high buildings many kinds of vegetables and berries are cultivated. And the demand of the nutritional supplement for the effective plant growth is also increasing. The general urban conditions are to be adapted for plant growth. A different hygroscopic and temperature-conditions after regions, sunshine and wind have strong influences on the plant growth and usually it is not optimal enough. It is because why a nutritional condition in soil for plant growth so important and essential. The usual compound-soil or -fertilizer cannot offer enough quantities of nutrients for plant growth and additional soil conditioner becomes more necessary. There are many kinds of soil conditioners like hydrogel in the market and we studied on Geohumus, Montigel and Geko, which are widely used in Europe and other countries. Water absorption and microbial immobilization with effective microorganisms were tested and compared. The EM solution was identified as bacteria, fungi and azotobacter etc. and they were immobilized at the soil conditioners at first. And the cultivated and immobilized at the soil conditioners EM-solution was added to the plant soil. 1 g of the soil conditioners absorbed ca. 20 g of water. The plant grew 10 cm more, got 3 times more branches and 2 times more fruits in the soil with soil conditioners immobilized with microorganisms. With water addition the plant with both conditions in the soil could stay fresh in comparison to without soil conditioners.

• 한국환경농학회지
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• 제16권1호
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• pp.80-93
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• 1997

Pesticide residues in soil could be affected to the growth of micro organisms and the activity of enzymes directly, and successively to the soil properties as pH, Eh and nitrogen metabolism. However, residues are diminished by degradation of soil microorganisms, run-off, leaching, volatilization, photodecomposition and uptake through crops. In this paper research results published in Korea were summarized about translocation of soil residues into crops, fates of residues in soil, effects to the activity of soil microorganisms and metabolic pathways of some pesticides. Generally speaking, pesticide residues in soil were not much affected to the agro-ecosystem except few chemicals. So it should be needed more further researches in this field, continuously.