• Korean Journal of Environmental Agriculture
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• v.13 no.3
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• pp.311-320
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• 1994

This study was conducted to investigate the biochemical properties of isolated bacteria, low temperature tolerant methane-producing clostridia which were selected for using them as inoculum to anaerobic fermentation of agricultural and livestock wastes at low temperature. The results were; 1. Low temperature tolerant methane-producing clostridia were isolated from the samples which showed the high methanogenesis rate by enrichment culture at low temperature in cellulose medium. These clostridia, Clostridium botulinum SRC-64, Clostridium scatologens SRC-91 and Clostridium tyrobutyricum SRC-100, were isolated from swampy sediment at latitude $56.9^{\circ}N$, lake sediment IV at latitude $55.0^{\circ}N$, and tidal land soil II at latitude $37.0^{\circ}N$, respectively. The optimum growth temperature for these isolates was $37^{\circ}C$ and the minimum, around $10^{\circ}C$. They all had detectable amount of $F_{420}$, specific coenzyme of methanogens. 2. As anaerobic fermentation products of glucose SRC-64 produced $H_2$, acetic, isovaleric and caproic acid, SRC-91 produced $H_2$, propionic, butyric, valeric, and caproic acid, and SRC-100 produced only acetic and propionic acid. The isolates were produced $CH_4$ ranged from 2.6 to 8.68 n moles/ml for 2 days at $13^{\circ}C$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.2
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• pp.181-187
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• 2014

Polycyclic aromatic hydrocarbons (PAHs) are a group of ubiquitous hazardous pollutants derived from fossil fuel, various combustion sources and pyrolysis of a wide range of plastics. Because PAHs can be uptake into crop plants, the inhibitory effects on rice and soybean plants were examined in greenhouse and growth chamber experiment. Soil-applied PAHs (phenanthrene of 0, 10, 30, 100 ppm) slightly reduced the plant height and dry weight both in transplanted rice and soybean plant. The inhibitory effect on growth was greater in soybean than rice. Plant height of soybean plants treated by 100 ppm was 58.9 cm and this value was 87.2% of untreated plant. In rice plant, the plant height was less inhibited (96.0% of untreated plant) by 100 ppm at 80 days after treatment (DAT). However, leaf chlorophyll content and chlorophyll fluorescence were less inhibited by PAHs at late growth stage (after heading) although the photosynthesis-related parameters were slightly inhibited from 20 DAT to 70 DAT. In agar medium experiment with infant seedlings, inhibition of seedling length and fresh weight by phenanthrene at 100 ppm were greater as compared to the experiment with adult plant in pot. Seedling length and fresh weight were reduced by 54.2% and 33.3% for rice and 27.9% and 13.2% for soybean, respectively. The results reflected that PAHs were more inhibitory during juvenile stage than adult stage and more inhibitory to rice plant than soybean for juvenile stage.

• Journal of Bio-Environment Control
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• v.21 no.1
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• pp.57-65
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• 2012

Fertilization is essential to seedling production in nursery culture, but excessive fertilization can contaminate surface and ground water around the nursery. The objective of this study was to find optimal fertilization practice of container seedling production for reducing soil and water contamination around the nursery without compromising seedling quality. This study was conducted to investigate chemical properties of the growth medium, growth performance, chlorophyll fluorescence, and chlorophyll contents of larch ($Larix$ $kaempferi$) growing under three different fertilization treatments (Constant rate, Three stage rate, and Exponential rate fertilization). Root collar diameter and height of larch were not significantly different among treatments even though the nutrient supply of the exponential treatment was half that of the constant and three stage treatments. Chemical properties of the growth medium showed the same trends as root collar diameter and height. The total biomass and seedling quality index (SQI) were higher at Constant than at other treatments, but both SQI of Constant and Exponential were not significantly different. Photochemical efficiency and chlorophyll contents were lower at Exponential than at other treatments, but not significantly different among treatments. Therefore, Exponential fertilization which is 50% fertilizer of other treatments would maximize seedling growth and minimize nutrient loss.

• Microbiology and Biotechnology Letters
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• v.26 no.2
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• pp.137-142
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• 1998

Helicobacter pylori is a Gram-negative bacterium which causes chronic gastritis and is associated with gastric ulcer, duodenal ulcer and gastric carcinoma. In the process of screening of antibacterial activities against H. pylori from soil microorganisms, fungus No. 60686 was isolated. After fermentation of No.60686, the antibacterial compound was isolated, purified and followed by extraction of mycelium with organic solvents, acetone and ethyl acetate, through silica gel chromatography, LH-20 gel chromatography and HPLC. As a result of the structural analyses of the compound by IR, $^1$H- and $^{13}$C-NMR, FAB/Mass spectrophotometer, the compound having the antimicrobial activity was identified as chaetoglobosin A ($C_{32}H_{36}N_2O_5$), a cytochalasan derivative. The antimicrobial activity of chaetoglobosin A was tested against Gram-positive and negative bacteria by paper disk method. Among the test strains of 9 Gram-positive bacteria and 18 Gram-negative bacteria containing 4 H. pylori strains, the growth of 4 H. pylori strains and 3 S. aureus strains (SG 511, 285 and 503) was only inhibited by chaetoglobosin A. Also it was shown that its growth inhibition against H. pylori strains was stronger than that against S. aureus strains at the treatment of the same concentration. Therefore it was concluded that chaetoglobosin A has a specific growth inhibition against H. pylori of the tested bacteria.

• Korean Journal of Environmental Agriculture
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• v.21 no.4
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• pp.269-273
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• 2002

A 0.19 hectare stream water purification demonstration wetland was constructed and planted with cattails from April 2001 to May 2001. Some portions of its bottom surfaces adjacent to levees have a variety of slope of 1:4 $\sim$ 1:15 and two small open water areas were installed in the wetland. These make its shape closer to a natural wetlant Nitrogen removal was a major objective of the wetlant Waters of Sinyang Stream flowing into Kohung Esturiane Lake located southern coastal region of Korean Peninsula were pumped and funneled into it. Volumes and water quality of inflow and outflow were analyzed from July 2001 through December 2001. Average inflow and outflow were 120 $m^3/d$ and 112 $m^3/d$, respectively. Hydraulic retention time was about 3.1 days. Average nitrate and total nitrogen removal rate for the early stage of the wetlands were 85.8 $mg/m^2/day$, 171.4 $mg/m^2/day$ respectively. Full establishment of cattails within a few years can develope litter-soil substrates and supply available carbon sources beneficial to the denitrification of nitrate. These can lead to increases of the nitrate retention rate. Short circuiting and dead zone areas which might be occurred due to the close-to-nature layout of the wetland were not observed during the monitoring period.

• Korean Journal of Weed Science
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• v.31 no.2
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• pp.183-191
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• 2011

Weeding effect was investigated based on the leaf stages to several different herbicide treatments for an integrated weed management of herbicide resistant Echinochloa oryzoides to ACCase and ALS inhibitors in a rice field. Efficacy of soil-applied herbicide treatments before resistant E. oryzoides occurred was very effective. Pentaxazon 5% SC showed over 98% of weeding effect although E. oryzoides were emerged 31 days after the treatment. Until the leaf stage of 2.5, five herbicides, azimsulfuron carfenstole 1.05% GR, bensulfuron-methyl benzobicyclone mefenacet 24.52% SC, bensulfuron-methyl fentrazamide 7% SC, bensulfuron-methyl mefenacet oxadiargyl 21.6% SC and mefenacet pyrazosulfuron-ethyl 3.57% GR showed perfect weeding effect. Benzobicyclone mefenacet penoxulam 21.5% SC and mefenacet pyrazosulfuron-ethyl 3.57% GR were effective at the leaf stage of 3.0. It is very important to select the right herbicides for timing and their systematic application for controlling of E. oryzoides resistant to ACCase- and ALS-inhibitors.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.972-976
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• 2006

비점오염은 일정한 오염원 없이 광범위한 지역에 쌓여 있는 오염물질이 강우 등에 의해 산발적으로 유출되는 비정형적인 오염을 말한다. 비점오염물질의 유출은 강우나 해빙에 의해 일시에 다량 발생되어 수계로 빠른 시간 내에 도달되게 되므로 인근 수계환경의 수질에 악영향을 미치게 되며, 이러한 오염물질을 효율적으로 처리하기 위해서는 발생원 가까이에서 수계에 도달하기 전에 저감하거나 유출과정에서 집수 처리하는 것이 가장 바람직하다. 본 연구에서는 이러한 비점오염물질의 저감을 위해 반응조를 이용한 실내실험을 실시하였다. 실내 실험장치는 아크릴로 제작 되었으며, 제원은 $1,000mm(L){\times}150mm(W){\times}300mm(H)$였다. 유입수는 시약을 이용하여 질소와 인의 농도를 고농도와 저농도로 조제하여 사용하였고, 유입은 미량 유량펌프를 이용하여 유입하였다. 토양의 오염물질의 처리 효율이 표면유출보다 하부유출에서 더 좋은 것으로 나타났기 때문에 하부유출의 양을 늘이기 위해 인위적으로 물의 흐름을 막는 정류벽을 설치한 계단형으로 구성하여 직선형과 비교하였다. 연구 결과, 단기간 저농도의 경우T-N, T-P부분에서 보면 직선형과 계단형의 표면유출 에서의 저감 효율이 T-N은 각각 -2.6 %, 2.4 %, T-P는 각각 -11.0 %, 52.9 %로 표면유출수의 오염저감효과가 개선되는 것으로 나타났다. 이는 방류벽 앞에 하부로 침투되었던 물이 표면으로 유출되면서 오염물질의 저감이 일어났기 때문으로 판단된다. 반면, 단면 및 하부유출수의 오염물질 농도는 증가한 것으로 나타났는데, 이는 토양내의 입경이 작은 silt나 clay보다 입경이 큰 모래나 자갈을 경유 하면서 오염물의 저감효과가 감소한 것으로 판단된다. 그러나 유입유량의 대부분이 표면으로 유출된다는 점을 고려할 때 표면유출수의 오염도를 낮추는 것이 유입오염물 저감효과에 보다 큰 효과가 있을 것으로 판단된다.문에 자료의 이상적 유지 관리가 이루어지며 복잡한 2차원 수질해석 모형을 수월하게 운영할 수 있는 시스템으로 개발하였다.제외하면, 부자측정 방법에 의한 유량산정시 가장 큰 오차원인은 홍수시 측정된 유속측선의 위치와 홍수 전후로 측정된 횡단면상의 위치가 일치하지 않는 점과, 대부분 두 측정 구간의 평균값을 대푯값으로 사용한다는 점이다. 본 연구는 다년간의 유량 측정 및 검증 경험과 자료를 토대로 현장에서 부자를 이용하여 측정된 측정성과를 정확도 높은 유량자료로 산정하는데 있어서의 문제점을 도출하고, 이로 인해 발생하는 오차를 추정하여 그 개선방안을 제시해 보고자한다. 더불어 보다 정확한 유량 산정을 위한 기준과 범주를 제시하고자 한다.리적 특성을 잘 반영하며, 도시지역의 복잡한 배수시스템 해석모형과 지표범람 모형을 통합한 모형 개발로 인해 더욱 정교한 도시지역에서의 홍수 범람 해석을 실시할 수 있을 것으로 판단된다. 본 모형의 개발로 침수상황의 시간별 진행과정을 분석함으로써 도시홍수에 대한 침수위험 지점 파악 및 주민대피지도 구축 등에 활용될 수 있을 것으로 판단된다. 있을 것으로 판단되었다.4일간의 기상변화가 자발성 기흉 발생에 영향을 미친다고 추론할 수 있었다. 향후 본 연구에서 추론된 기상변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기 위한 연구가 필요할 것이다.게 이루어질 수 있을 것으로 기대된다.는 초과수익률이 상승하지만, 이후로는 감소하므로, 반전거래전략을 활용하는 경우 주식투자기간은 24개월이하의 중단기가 적합함을 발견하였다. 이상의 행태적 측면과 투자성과측면의 실증결과를 통하여 한국주식시장에 있어서 시장수익률을 평균적으로 초과할 수 있는 거래전략은 존재하므로 이러한 전략을 개발 및 활용할 수 있으며, 특히, 한국주식시장에 적합한 거래전략은 반전거래전략이고, 이 전략의 유용성은 투자자가 설정한 투자기간보다 더욱 긴 분석기간의 주식가격정보에 의하여 최대한 발휘될 수 있음을 확인하

• Korean Journal of Medicinal Crop Science
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• v.5 no.3
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• pp.237-242
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• 1997

The experiment was conducted to find causes of rooting failure in divided crown of peony cultivation. The results were as follows : In farmer s fields, damage rate of rooting failure in divided crown of peony was 32% as non-sprouting 5.6%, withering after sprouting 20.7%, and wilting after sprouting 5.7%, repectively. Damage degree in farmer s fields was followed, above 70% by 4%, 41 to 70% by 17%, 11 to 40% by 45% per total field area, respectively. It was caused by rooting failure. Damage rate of rooting failure as affected by different planting time was 18.2% for planting in autumn, 42.9% for planting in spring, and damage in divided crown was higher than in seedling. As periods to planting were prolonged, growth and yield were larger poorly, treatment with seminal-root sterilization and soil insecticide showed good growth and rooting but untreated control was very poor. Main cause of rooting failure in divided crown of peony was disease, Cylindrocarpon sp. and low quality of seeds.

• Korean Journal of Organic Agriculture
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• v.11 no.3
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• pp.65-73
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• 2003

This study was conducted to investigate the effect of microbial liquid manure(MLM) on the growth and yield characteristics of Altari radish (Raphanus sativus L.). MLM 1,000mg$.$L$^{-1}$ MLM 2,000mg$.$L$^{-1}$ and MLM 1,000mg L$^{-1}$ + microbial fermentation compost(MFC) 600kg/10a were treated. MLM was sprayed on leaves at 10, 20, and 40 days after planting. Leaf length and width of radish in all microbial fertilizer treatments were more vigorous than that of control significantly. Number of leaves was great in order of 1,000 mg$.$L$^{-1}$ MLM+600kg/10a MFC 〉2,000mg$.$L$^{-1}$ MLM〉1.000mg$.$L$^{-1}$ MLM. SPAD reading value was increased with treatments of 2,000mg$.$L$^{-1}$ MLM and 1,000mg$.$L$^{-1}$ MLM+600kg/10a MFC. Root length and weight of all the microbial fertilizer treatments tended to increase compared with control, and 1,000mg$.$L$^{-1}$ MLM+600kg/10a MFC treatment was the most effective.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1265-1265
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• 2001

The organic materials included in excreta of livestock are important resources for organic manure and for improving soil quality, although there is still far from effective using. One reason for this is still unclearly standard of quality for evaluation of manure made from excreta of livestock. Therefore, the objective of this study is to develop rapid and accurate analytical method for analyzing organic compositions of manure made from excreta of livestock, and to establish quality evaluation method based on the compositions predicted by near infrared reflectance spectroscopy (NIRS). Sixteen samples of manure, each eight samples prepared from two treatments, were used in this study. The manure samples were prepared by mixing 560 kg feces of swine,60 kg sawdust with moisture content was adjusted to be 65%. The mixture was then keep under two kinds of shelter, black and clear sheets, as a treatment on the effect of sunlight. Samples were taken in every week (form week-0 to 7) during the process of manure making. Samples were analyzed to determine neutral detergent fiber (NDF), acid detergent fiber (ADF) and acid detergent lignin (ADL) by detergent methods, and organic cell wall (OCW) and fibrous content of low digestibility in OCW (Ob) by enzymatic methods. Biological oxygen demand (BOD) was analyzed by coulometric respirometer method. These compositions were carbohydrateds and lignin that were hardly digested. Spectra of samples were scanned by NIR instrument model 6500 (Pacific Scientific) and read over the range of wavelength between 400 and 2500nm. Calibration equations were developed using eight manure samples collected from black sheet shelter, while prediction was conducted to the other eight samples from clear sheet shelter. Accuracy of NTRS prediction was evaluated by correlation coefficients (r), standard error of prediction (SEP) and ration of standard deviation of reference data in prediction sample set to SEP (RPD). The r, SEP and RPD value of forage were 0.99, 0.69 and 7.6 for ADL, 0.96, 1.03 and 4.1 for NDF, 0.98, 0.60 and 4.9 for ADF, 0.92, 1.24 and 2.6 for Ob, and 0.91, 1.02 and 7.3 for BOD, respectively. The results indicated that NIRS could be used to measure the organic composition of forage used in manure samples.