• Journal of Microbiology and Biotechnology
• /
• 제30권11호
• /
• pp.1688-1696
• /
• 2020

Soil physical and chemical characteristics, soil potential denitrification rates (PDR), community composition and nirK-, nirS- and nosZ-encoding denitrifiers were studied by using MiSeq sequencing, quantitative polymerase chain reaction (qPCR), and terminal restriction fragment polymorphism (T-RFLP) technologies base on short-term (5-year) tillage field experiment. The experiment included four tillage treatments: conventional tillage with crop residue incorporation (CT), rotary tillage with crop residue incorporation (RT), no-tillage with crop residue retention (NT), and rotary tillage with crop residue removed as control (RTO). The results indicated that soil organic carbon, total nitrogen and NH₄⁺-N contents were increased with CT, RT and NT treatments. Compared with RTO treatment, the copies number of nirK, nirS and nosZ in paddy soil with CT, RT and NT treatments were significantly increased. The principal coordinate analysis indicated that tillage management and crop residue returning management were the most and the second important factors for the change of denitrifying bacteria community, respectively. Meanwhile, this study indicated that activity and community composition of denitrifiers with CT, RT and NT treatments were increased, compared with RTO treatment. This result showed that nirK, nirS and nosZ-type denitrifiers communities in crop residue applied soil had higher species diversity compared with crop residue removed soil, and denitrifying bacteria community composition were dominated by Gammaproteobacteria, Deltaproteobacteria, and Betaproteobacteria. Therefore, it is a beneficial practice to increase soil PDR level, abundance and community composition of nitrogen-functional soil microorganism by combined application of tillage with crop residue management.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
• /
• pp.250-253
• /
• 2002

Remediation of groundwater using zero valent iron filings has received considerable attention in recent years. However, zero valent iron is gradually transformed to iron(III) oxides at permeable reactive barriers, so the reduction of iron(III) oxides can enhance the longevity of the reactive barriers. In this study, microbial reduction of Fe(III) was performed in anaerobic condition. A medium contained nutrients similar to soil solution. The medium was autoclaved and deoxygenated by purging with 99.99% $N_2$ and pH was buffered to 6, while the temperature was regulated as 2$0^{\circ}C$. Activity of iron reducing bacteria were not affected by chlorinated organics but affected by iron(III) oxide. Although perchloroethylene(PCE) was not degraded with only ferric oxide, PCE was reduced to around 50% with ferric oxide and microorganism. It shows that reduced iron can dechlorinate PCE.

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2002년도 생물공학의 동향 (X)
• /
• pp.403-406
• /
• 2002

This experimental shows the possibility of using as biofertilizer, which convert insoluble inorganic phosphate salts to plant-usable phosphate type by immobilized microorganism with calcium alginate. In the case of culture of P. agglomerans on constant medium pH, phosphate was produced 357 mg/L after 18hrs. And in the case of culture of immobilzed P. agglomerans bead, phosphate was produced maximum 295.6 mg/L after 120 hrs. Also as using rock phosphate as insoluble phosphate salts, phosphate was respectably produced 190.3 and 195.2 mg/L after 36 hrs at free cells and immobilized cells. In our experiments, the using soils contained 23.16 g-P/kg-soil total phosphate and 3.76 g-P/kg-soil soluble phosphate. The result of 1g immobilized bead seeding, soluble phosphate was produced maximum 6.14 g-P/kg-soil phosphate and this value was increased continuously.

• Mycobiology
• /
• 제42권4호
• /
• pp.401-404
• /
• 2014

A new recorded species of Mortierella was recovered during the investigation of fungal communities in soil samples collected from different locations of Gangwon-do, Korea. The species was identified and described as Mortierella alpina on the basis of phylogenetic analysis of internal transcribed spacer sequences and morphological characteristics. This species has not been officially reported from Korea thus far.

• 한국유기농업학회지
• /
• 제12권4호
• /
• pp.399-409
• /
• 2004

This study was conducted to investigate the effect of different concentrations of microbial products on growth of chinese cabbage and microorganisms in soil. Two different levels of microbial products, such as 50 times and 100 times diluted solutions of chitosan, wood vinegar and EM activity liquid, were treated for foliar application. the results were summarized as follows : Among foliar applications of microbial products, 100 times diluted solution of chitosan was effective on growth of chinese cabbage comparing to other levels of dilutions and untreated control plot. The number of microorganism in the soil tended to increase under the treatment of microbial products compared to control plot. Especially, the numbers of the bacteria and actinomycetes were estimated $73.67{\times}10^3$ CFU/g and $34.00{\times}10^3$ CFU/g, respectively, under the treatment of 100 times diluted solution of chitosan.

• 한국환경농학회지
• /
• 제38권4호
• /
• pp.262-268
• /
• 2019

토양에서 유기자원의 무기화 특성을 구명하기 위하여 질소함량별로 볏짚, 우분퇴비, 균배양체, 유박, 아미노볼 등 총 5가지를 각각 처리하여 128일 동안 실내 항온배양실험을 실시하였으며, 이 분석결과를 질소 무기화 모형에 적용하여 유기자원의 질소 무기화 양상을 구명하였다. 항온배양 기간 동안 유기자원의 질소 순 무기화율은 질소함량이 가장 높은 아미노볼에서 가장 높았고, 질소함량이 가장 낮은 볏짚에서 가장 낮았다.잠재적 질소 무기화율은 전질소 함량과는 양의 상관관계(0.96)가 인정되었다. 무기화 속도상수 k는 유기자원의 유기물(-0.96) 및 탄소함량(-0.97)과 음의 상관관계가 인정되었다. 모형에 의해 추정된 1작기 동안의 질소 무기화율은 볏짚 6.6%, 우분퇴비 11.6%, 균배양체 30.9%, 유박 70.7%이었으며 아미노볼은 81.0%를 나타냈다. 질소 무기화율은 유기자원의 종류 또는 질소함량에 따라 다르게 나타나 질소 무기화율을 유기자원의 질소 공급 특성을 결정하는 지표로 사용할 수 있다. 질소함량이낮거나 발효과정을 거치는 퇴비 등의 유기자원은 퇴비화 과정에서 유기태 질소가 안정화되어 질소의 무기화율이 무발효 유기자원보다 낮으므로 시비량 결정시 양분공급의 목적보다는 토양 물리성 개량을 목적으로 사용하는 것이 바람직하다.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제18권3호
• /
• pp.1-10
• /
• 2013

This study was performed to summarize application of ${\delta}^{13}C$, ${\delta}^{37}Cl$ and ${\delta}D$ of trichloroethylene (TCE) to studies on environmental forensic field regarding identification of TCE sources and evaluation of contribution of TCE to groundwater using data collected from literatures. ${\delta}^{13}C$, ${\delta}^{37}Cl$ and ${\delta}D$ of TCE give some information regarding sources of TCE because they show specific value according to manufacturing method. Also, TCE do not show a significant isotopic fractionation owing to adsorption and dilution. The isotopic fractionation mainly occurs by biodegradation. In addition, isotopic fractionation factor for TCE is different according to a kind of microorganism participated in biodegradation. However, the isotopic data of TCE have to be applied with chemical compositions of TCE and other hydrogeologic factors because isotopic fractionation of TCE is influenced by various factors.

• 한국토양비료학회지
• /
• 제49권5호
• /
• pp.440-448
• /
• 2016

Nonpoint sources of pollution (NPS) is defined as diffuse discharges of pollutants (e.g., nutrient, pesticide, sediment, and enteric microorganism) throughout the natural environment and they are associated with a variety of farming practices. Previous studies found that water soluble anionic polyacrylamide (PAM) is one of the highly effective measures for enhancing infiltration, reducing runoff, preventing erosion, controlling nonpoint source of pollutants, and eventually protecting soil and water environment. Potential benefits of PAM treatment in agricultural soil and water environments have been revealed by many research and they include low cost, easy and quick application, and suitability for use with other Best Management Practices (BMPs) for NPS control. This study reviews the various applications of PAM and discusses its further potentials in agricultural environment.

• 한국환경농학회지
• /
• 제19권4호
• /
• pp.270-275
• /
• 2000

토양미생물군인 Miraculous soil-Microorganisms (MS균) 제제를 음식폐기물에 처리 후 발효공정에 따른 아플라톡신의 잔존 유무 분석, 열량 아미노산 및 지방산 조성분석을 통해 양돈사료화를 위한 효율적 처리방법에 대한 자료를 얻고자 실시하였다. 음식폐기물의 MS균 발효 후 calorimeter를 이용한 열량측정 결과 건물 1g당 평균 7.599 Kcal D.M 정도의 높은 열량을 가지는 것으로 나타났으며, MS균 첨가 후 각 발효공정의 모든 시료에서 아플라톡신은 검출되지 않았다. 음식폐기물내 총 아미노산의 함량은 쌀겨 (10%) 및 어분 (5%) 첨가 후 MS균에 의한 3주간 혐기발효 하였을 때 $92.99\;mg{\cdot}g^{-1}$으로 저온 발효 후 보다 약 18.5%의 아미노산 함량이 증가되었다. MS균에 의한 최종 발효 후 필수아미노산 함량은 $34.43\;mg{\cdot}g^{-1}\;D.M$ 이었으며, leucine, phenylalanine, isoleucine 및 thereonine이 높은 구성비율을 보였다. 비필수아미노산 함량은 $58.66\;mg{\cdot}g^{-1}\;D.M$이었고 proline과 glutamic acid의 함량이 상대적으로 높았다. 지방산 조성에 있어서는 palmitic acid, oleic acid 및 palmitoleic acid의 함량이 상대적으로 높았으며, 지방산 함량 역시 혐기숙성 발효에 의해 증가되었다. 이상의 결과들은 음식폐기물을 MS균에 의해 발효처리하였을때 양돈사료로서의 충분한 열량을 함유하고 있으며, 아플라톡신으로부터 안전함을 보여주며, MS균에 의한 혐기발효를 통해 음식폐기물내 단백질 및 지방의 가수분해를 촉진시킬 수 있음을 잘 보여주었다.

• 한국유기농업학회지
• /
• 제19권1호
• /
• pp.93-107
• /
• 2011

유기 배 과수원의 생물종 다양성을 조사하기 위해 토양 미소동물은 토양채취를 하였으며 지상부의 생물 조사는 pitfall 트랩, malaise 트랩, 유아등을 사용하여 채집하였다. 토양채취에서는 유기재배에서 37종 1,184마리, 관행 재배 28종 501마리였으며 pitfall 트랩에서는 각각 38종 648마리, 29종 440마리였다. malaise 트랩과 유아등에서는 각각 55종 650마리, 47종 508마리와 23종 201마리, 9종 42마리였다. 토양채취에서 톡토기목이 389마리로 많이 채집되었는데 관행재배지 보다 5배 이상 많이 채집되었으며 pitfall 트랩에서도 183마리로 3배 이상 채집되어 지표생물로 선발되었다. 토양미소동물의 유기재배지의 종 다양도는 3월에 1.956, 8월에 2.638로 관행의 1.426, 2.011보다 더 높아 유기 재배지에서 생물 다양성이 더 높았다. Pitfall 트랩에서 주로 출현한 종들은 거미류, 톡토기류, 딱정벌레였다. 딱정벌레 중에 관행재배지에는 점박이먼지벌레, 폭탄먼지벌레가 유기재배지에서는 큰넓적송장벌레가 지표생물이 될 가능성이 높았다. malaise 트랩에 의한 곤충종은 벌목, 파리목이 많이 채집되었으며, 그중에서 벌류는 고치벌과 맵시벌이 주를 이루었다. 지상부 생물의 종 다양성 조사 결과, pitfall 트랩의 종다양도가 유기재배지에서 2.952, 관행 2.587이었으며, malaise 트랩은 유기 3.120, 관행 2.398, 유아등은 유기 2.010, 관행 1.507로 나타나 malaise 트랩에서의 종 다양도가 가장 높았다.