• Applied Biological Chemistry
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• 제27권
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• pp.68-79
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• 1984

An increased population and rapidly expanding industrial development have led to enormous amounts of various domestic and industrial wastes. The proper disposal of ever-increasing wastes is a growing global problem. Land treatment is one of the rational approaches that are environmentally safe and economically practical. It has long been practised in many sites. Recycling of industrial wastes on agricultural land can provide better possible means for maintaining environmental quality and utilizing waste-resources. Even though industrial wastes are beneficial as soil amendment and fertilizer, they have some limitation on land application because of wide variability as well as physicochemical problem in their composition. A direct application of solid and liquid wastes on land is being practised in Korea and some experimental results are presented. The direct application of fermentation waste on rice resulted in a 6 percent yield increase. Another organic residue from glutamic acid fermentation is widely used not only as a direct application as a liquid fertilizer but also for a raw material of organic compound fertilizer. These wastes are much promising as sources of plant nutrients, since they have large amounts of nutrients, especially nitrogen with few toxic metals. On the other hand, fertilizers developed from inorganic industrial wastes include calcium silicate, calcium sulfate and ammonium sulfate. The calcium silicate fertilizer simply produced from slag, by-product of iron and steel manufacturing plant is one of the most successful example of the conversion of wastes to fertilizer and slag production capacity totals to over three million MT/year. About 200,000 MT of calcium silicate fertilizer is currently applied in the paddy rice every year. Calcium sulfate, a waste from the wet phosphoric acid process is to some extent used as a filler of compound fertilizers but quite large quantites are directly applied for the reclamation of tidal flat.

• 한국환경과학회지
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• 제6권2호
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• pp.173-182
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• 1997

The bacterial strains, which utilizes 2,4,4'-trichloro-2'-hydroxydiphenyl ether(TCHDPE) as a sole carbon source, were isolated by selective enrichment culture from soil samples of industrial waste deposits. The bacterium that showed the highestt biodegradation activity was designated as EL-O47R The isolated strain EL-O47R was Identified as the genus Pseudomonas from the results of morphological, cultural, and biochemical tests. The optimum conditions of medium for the growth and the degradation of TCHDPE were TCHDPE 500 ppm, (NH4)2SO4 0.1% as the nitrogen source, initial pH 7.0±0.1, and 37℃, respectively. In this conditions, the regradation rate of TCHDPE was about 97%. Pseudomonas sp. EL-O47R was tested for resistance to several metal compounds and antibiotics. Pseudomonas sp. EL-O47R was moderately grown to Cd(NO3)2, ZnCl2, AgSO4, CuSO4 and HgCl2. This strain was sensitive to rifampicin and kanamycln but resistant to ampicillin, penicillin, tetracyclin and chloramphenlcol. Pseudomonas sp. EL-O47R was grown structurally related com- pounds and potential metabolites of TCHDPE, and has the stability on TCHDPE biodegradation.

• 환경생물
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• 제27권4호
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• pp.384-390
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• 2009

새로운 항진균성 항생물질개발을 목적으로 고추탄저병균인 Colletotrichum gloeosporioides에 대한 항생활성을 가지는 미생물을 토양으로부터 분리하여 동정한 결과, Bacillus sp. CJ-1로 동정하였다. 항생물질의 생산을 위한 배양조건을 검토한 결과, glucose 1.5% (w/v), yeast extract 0.5% (w/v), pH 6.0의 배지를 사용하여 $35^{\circ}C$에서 72시간 진탕 배양하였을 때 항진균활성이 가장 좋았으며, 이때 피검균인 C. gloeosporioides에 대한 배양액의 생육저지환은 약 27.8mm로 최대의 활성을 보여주었다. 피검균인 C. gloeosporioides에 대한 배양액의 생육저지현상을 현미경을 통해 관찰한 결과 배양액 $12.5\;{\mu}L\;mL^{-1}$이상의 농도에서 뚜렷한 생육저해현상을 관찰할 수 있었으며 이는 피검균 포자의 발아억제현상과 연관되어 있을 것으로 추측된다.

• 한국작물학회지
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• 제45권3호
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• pp.163-166
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• 2000

본 연구는 제주도에 있어서 인산 시비량 차이(0, 5, 15, 25, 35 kg/10a)에 따른 차풀의 생육반응, 수량성 및 사료가치를 검토하고, 적정 인산 시비량을 구명하기 위하여 1998년 3월부터1998년 9월까지 시험하였다. 개화기까지의 일수는 인산 시비량이 증가됨에 따라 점차적으로 지연되었다 초장, 본당 분지수 및 엽수, 경직경, 엽록소 측정치 등은 인산 시비량이 증가됨에 따라 점차적으로 증가하였으나, 본당 고엽수는 적어지는 경향이었다. 생초수량은 무인산구에서 3,291kg/10a이었으나 인산 시비량이 많아짐에 따라 점차적으로 증가되어 25kg/10a과 35kg/10a 시비구에서는 각각 10a당 5,200 kg과 5,230kg이었으나, 두처리간에는 유의성이 없었다. 건초, 조단백질 및 TDN수량도 생초수량의 변화와 비슷한 경향이었다. 조단백질, 조지방, 가용성무질소물, TDN 함량은 인산 시비량이 증가됨에 따라 많아지는 경향이었으나, 조회분과 조섬유 함량은 낮아졌다.

• 한국초지조사료학회지
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• 제12권4호
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• pp.201-210
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• 1992

This study was designed to investigate the content of inorganic nitrogen($NH_4$, $NO_3$) and its change in the 7 different sites; the permanent meadows of alfalfa, orchardgrass, and reed canarygrass, the fields of rye. corn, rice and a mountain region. the results from this study were summarized as follows; 1. The contents of ammonium and nitrate in meadows were 15.89-16.46 and 1.32-1.86ppm, respectively, showing the lower level than in other sites and no significant diffirences among three meadows. 2. In the rice field, the average content of ammonium(7.19ppm) was the highest among all sites, but the content of nitrate(1 l.l7ppm) was the lowest. In addition, almost all of nitrate were spreaded around the surface. 3. In the mountain region, the content of $NH_4$(5.79ppm) was slightly high, but the content of nitrate ( 15.18ppm) was very low. 4. In the rye field. the average content of $NO_3$ was 35.46ppm and show the highest (92.63ppm) at the deep part of soil in the specific season, but it decreased with increasing temperature. 5. In the corn field, which kept bare after harvesting the corn silage, the content of $NO_3$ was high, regardless of seasons and depths, and increased up to maximum of 103ppm. 6. The ground water concentrations of $NO_3$ were not more than 50ppm in the pasture. In the vegetable house, they were less than 30 ppm during the winter and spring and were 80-100ppm during the summer and fall. 7. The concentrations of $NO_3$ in Han river water were lower during the winter and spring(20-30ppm) and higher dxring the summer and fall (50-90ppm).

• 상하수도학회지
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• 제32권3호
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• pp.221-233
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• 2018

Two climate change scenarios, the RCP (Representative Concentration Pathways) 4.5 and the RCP 8.5 in the fifth Assessment Report (AR5) by Intergovernmental Panel on Climate Change (IPCC), were applied in the Yocheon basin area using the SWAT (Soil and Water Assessment Tool) model to estimate changes in flow rates and pollutant loadings in the future. Field stream flow rate data in Songdong station and water quality data in Yocheon-1 station between 2013~2015 were used for model calibration. While $R^2$ value of flow rate calibration was 0.85 and $R^2$ value of water qualities were in the 0.12~0.43 range. The total study period was divided into 4 sub periods as 2030s (2016~2040), 2050s (2041~2070) and 2080s (2071~2100). The predicted results of flow rates and water quality concentrations were compared with results in calibrated periods, 2015s (2013~2015). In both RCP scenarios, flow rate and TSS (Total Suspended Solid) loadings were estimated to be in increasing trend while TN (Total Nitrogen) and TP (Total Phosphorus) loadings showed decreasing patterns. Also, flow rates and pollutant loadings showed larger differences between the maximum and the minimum values in RCP 4.5 than RCP 8.5 scenarios indicating more severe effect of drought and flood, respectively. Dependent on simulation period and rainfall periods in a year, flow rate, TSS, TN and TP showed different trends in each scenario. This emphasizes importance of considerations on time and space when analyzing climate change impacts of each variable under various scenarios.

• 미생물학회지
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• 제40권2호
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• pp.139-146
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• 2004

일반 토양과 부엽토, 퇴비로부터 alkaline cellulase 생성이 우수한 균주를 분리한 후 형태적, 배양학적 및 생화학적 동정을 실시한 결과 호알칼리성 Bacillus sp. HSH-810 균주인 것으로 판명되었다. 분리균 Bacillus sp. HSH-810의 생육과 효소 활성은 $30^{\circ}C$와 pH 10.0에서 가장 높은 것으로 나타났다. 본 균주는 배지 중에 탄소원과 질소원, 무기염으로 1.0%의 CMC와 0.5%의 peptone, 0.02%의 $CaC1_2$, $CoC1_2$를 사용하였을 경우 최대의 alkaline cellulase생산성을 나타내었다. 효소의 최적 활성 pH와 온도는 각각 10.5와 $50^{\circ}C$였다. 이 효소는 pH 6.0-13.0과 $50^{\circ}C$의 온도에서 매우 안정하였다. 효소액에 계면활성제를 첨가하여 효소 활성을 측정한 결과, 효소액은 sodium-$\alpha$-olefin sulfonate (AOS)와 sodium dodecyl sulfonate (SDS), Tween 20, Tween 80에 대하여 안정성 이 높은 특징을 보였으나 0.1%의 linear alkyl-benzene sulfonate (LAS)를 첨가한 경우에는 효소 활성이 심하게 저해되었다.

• Journal of Ecology and Environment
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• 제36권1호
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• pp.31-38
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• 2013

Annual ring formation is considered a source of information to investigate the effects of environmental changes caused by temperature, air pollution, and acid rain on tree growth. A comparative investigation of annual ring growth of Cryptomeria japonica in relation to environmental changes was conducted at two sites in southern Korea (Haenam and Jangseong). Three wood disks from each site were collected from stems at breast height and annual ring growth was analyzed. Annual ring area at two sites increased over time (p > 0.05). Tree ring growth rate in Jangseong was higher than that in Haenam. Annual ring area increment in Jangseong was more strongly correlated with environmental variables than that in Haenam; annual ring growth increased with increasing temperature (p < 0.01) and a positive effect of $NO_2$ concentration on annual ring area (p < 0.05) could be attributed to nitrogen deposition in Jangseong. The correlation of annual ring growth increased with decreasing $SO_2$ and $CO_2$ concentrations (p < 0.01) in Jangseong. Variation in annual growth rings in Jangseong could be associated with temperature changes and N deposition. In Haenam, annual ring growth was correlated with $SO_2$ concentration (p < 0.01), and there was a negative relationship between precipitation pH and annual ring area (p < 0.01) which may reflect changes in nutrient cycles due to the acid rain. Therefore, the combined effects of increased $CO_2$, N deposition, and temperature on tree ring growth in Jangseong may be linked to soil acidification in this forest ecosystem. The interactions between air pollution ($SO_2$) and precipitation pH in Haenam may affect tree growth and may change nutrient cycles in this site. These results suggested that annual tree ring growth in Jangseong was more correlated with environmental variables than that in Haenam. However, the further growth of C. japonica forest at two sites is at risk from the long-term effects of acid deposition from fossil fuel combustion.

• 한국미생물·생명공학회지
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• 제10권2호
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• pp.109-115
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• 1982

토양으로 부터 diaminododecane 자화균 DAD2-2주를 분리하여 검토한 결과 Corynebacterium속으로 동정되었으며 DAD2-2주의 alkane 유도체에 대한 생육특성조사에서 putrescine dihydrochloride, dodecanethiol, dodecane. laurylamine등은 탄소원으로 이용될 수 있었으나 thioanisole, decanedithiol, dicyanooctane, 1aurylcyanide, dichlorodecane등은 이용되지 못하였다. Emulgen 25ppm을 DAD배지에 첨가하였을 경우 DAD2-2주에 의한 diaminododecane 자화가 현저하게 촉진되었으며 diaminododecane자화시 생성되는 중간생성물은 ethyl $\alpha$-ketoglutarate로 동정되었다. 그러나 diaminododecane을 탄소원 뿐만 아니라 질소원으로도 이용하였을 경우에 있어서는 ethyl $\alpha$-ketoglutarate와는 다른 생성물을 생성하였으며 diaminododecane 대신 glucose, putrescinc, n-dodecane을 생육기질로 이용하였을 때에도 ethyl $\alpha$-ketoglutarate와는 다른 생성물을 생성하였다. 또한 resting cell을 이용하여 alkane 유도체를 co-oxidation시키는 과정에서도 ethyl $\alpha$-ketoglutarate와는 상이한 생성물이 생성되었다.

• Journal of Microbiology and Biotechnology
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• 제30권6호
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• pp.839-847
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• 2020

In the present study, an anaerobic microbial consortium for the degradation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) was selectively enriched with the co-addition of RDX and starch under nitrogen-deficient conditions. Microbial growth and anaerobic RDX biodegradation were effectively enhanced by the co-addition of RDX and starch, which resulted in increased RDX biotransformation to nitroso derivatives at a greater specific degradation rate than those for previously reported anaerobic RDX-degrading bacteria (isolates). The accumulation of the most toxic RDX degradation intermediate (MNX [hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine]) was significantly reduced by starch addition, suggesting improved RDX detoxification by the co-addition of RDX and starch. The subsequent MiSeq sequencing that targeted the bacterial 16S rRNA gene revealed that the Sporolactobacillus, Clostridium, and Paenibacillus populations were involved in the enhanced anaerobic RDX degradation. These results suggest that these three bacterial populations are important for anaerobic RDX degradation and detoxification. The findings from this work imply that the Sporolactobacillus, Clostridium, and Paenibacillus dominant microbial consortium may be valuable for the development of bioremediation resources for RDX-contaminated environments.