• Journal of Korean Society of Environmental Engineers
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• v.29 no.9
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• pp.1003-1012
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• 2007

In this study, we analyzed the release differences for some critical pollution compounds according to the surrounding conditions in order to predict water quality due to the sedimental releases and the release characteristics at different sedimental locations in Lake Leewon, in Tae-An area. COD, nitrogens and phosphates were analyzed using the standard methods for water quality, based on high chloride ion concentration(greater than 2,000 ppm). For COD, the release rate increased in the anoxic basin but almost the same in the oxic basin. For $NH_3$-N, the release rate decreased in the oxic basin as you go A through C point meanwhile, for $NO_3$-N and T-N, the tendency was reversed because of nitrification of them. In the anoxic basin, the release rates of $NH_3$-N and $NO_3$-N went up with A through C path. However, the release rate of T-N was found to decrease. Also, for $PO_4$-P and T-P, the release rates in the oxic basin were lowest at B point mainly because the phosphates were at less released in the highly $O_2$ concentrated environment. In the anoxic reactor, $PO_4$-P was released similarly regardless of the sampling points. In summary, the release rates in the oxic reactor were greater than those in the anoxic reactor for COD and $NO_3$-N. For the other components, the anoxic basin generated the higher release rates.

• Korean Journal of Soil Science and Fertilizer
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• v.26 no.2
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• pp.121-126
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• 1993

The behaviors of inorganic nitrogen derived from solid animal waste in soil has been received too much concern partly because nitrate which occurred from nitrification can act as a pollutant to soil and groundwater and partly because the loss of nitrogen from surface soil by downward movement of water is disadvantageous in the view of plant nutrient. This present study was conducted to get fundamental imformations on nitrogen behavior and to provide improved basical concepts on the management of animal waste. Fresh or fermented pig manure was mixed with a sandy loam soil in the ratio of 2:1(soil:pig manure), packed into test tube and incubated at $30^+/-1^{\circ}C$ for 8 weeks under aerobic- or anaerobic condition. Sample tubes were taken at the one week interval and analyzed on pH, the amount of $CH_4$ produced under anaerobic condition and inorganic nitrogen. The pH of soil treated with fresh pig manure under anaerobic condition was lowered by 1.87 unit compared to that of under aerobic condition, but at the treatment with fermented pig manure, pH change was very little between aerobic and anaerobic condition. The coefficients of regressional equations which were obtained from pH and incubation time were -0.114 in fresh pig manure and -0.089 in fermented pig manure, and the extent of pH decrease due to incubation was greater in fresh pig manure than that of fermented pig waste. No differences in the amounts of $CH_4$ produced under anaerobic condition between fresh and fermented pig manure was observed until 3 weeks of incubation, however, after that the amount of $CH_4$ produced in fresh pig manure was abruptly increased and cumulative amont of $CH_4$ was reached 8.6 mole/g. K values on $CH_4$ production in fresh and fermented pig manure was 0.211 mole/g/day and 0.046 mole/g/day, respectively, for 5 weeks from the 3rd to the 8th week. $NH_4-N$ concentration at aerobic condition with fresh pig manure treatment was lowered by passing time of incubation, but $NO_3-N$ concentration was elevated from 11.2 ppm at initial state to 67.3 ppm after incubation and this trend on $NH_4-N$, $NO_3-N$ concentration was very similar to the treatment of fermented pig manure. While $NH_4-N$ concentration under anaerobic condition was greatly increased. $NO_3-N$ concentartion was not only very low but also no great changes, that was ranged from 4 to 8 ppm.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.12
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• pp.1345-1352
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• 2007

To predict the effects of nutrient releasing on the water quality of Namyang Reservoir, nutrient releasing rates from sediments in oxic and anoxic conditions were estimated in a small microcosm. Organics and nitrogens were not released. The releasing pattern of inorganic phosphate and total phosphorus was depend on the oxygen concentration. The releasing rate of inorganic phosphate and total phosphorus in oxic condition was $1.01\sim2.48$ and $2.14\sim3.54$ mg-P/$m^2$/day, respectively. It was high in the upstream sediments indicating the particles containing easily degradable organic compounds are flowed into the area. Because the depth of Namyang Reservoir at the downstream adjacent to the Dam is $7\sim14$ m, the condition of most area of sediment surface will be oxic. Based on these results, the appropriate counterplans are required to reduce phosphorus release in oxic conditions to control water pollution.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.7
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• pp.738-745
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• 2006

In this research, the decolorization mechanisms of dye wastewater were divided into two pathways, one was physicochemical sorption to biomass flocs and the other was biological removal by microbial metabolisms. Batch tests were conducted to examine the reaction conditions, anaerobic and aerobic conditions, types and dose of cosubstrates, and to confirm the mechanisms of decolorization through the biosorption tests using the activated sludge and the autoclaved deactivated sludge. From the tests, the decolorization efficiencies of dye wastewater were 102 ${\Delta}$unit/g MLSS under the aerobic condition and 123 ${\Delta}$unit/g MLSS under the anaerobic condition, and organic removals were 82 $mg{\Delta}$COD/gMLSS and 75 $mg{\Delta}$COD/gMLSS respectively. Acetate was the more efficient cosubstrate than the domestic wastewater in the decolorization step. In addition the removal of colors and organics was increased with cosubstrates dosage. And $20.3{\sim}37.3$ ${\Delta}$unit/g MLSS was removed by the autoclaved sludge and $102.0{\sim}159.0$ ${\Delta}$unit/g MLSS by the activated sludge. The physicochemical sorption was dominant in the beginning of biosorption tests, and the biological decolorization was increased with a cosubstrate in the course of time.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1992.05a
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• pp.23-23
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• 1992

횐 쥐에서 sulfotransferase 양성균주를 검색한 결과 호기성 조건보다는 혐기성 조건의 균이 많은 것으로 나타났다. 이러한 곁과는 장내미생물의 대부분이 혐기성균이라는 것과도 일치하는 것이다. 검색용 배지에서 형광을 나타내는 Sulfotransferase를 생산하는 4개 균주에서 가장 활성이 높은 k-36균주에 대하여 동정하였다. K-36 균주는 혐기적 및 호기적 양조건에서 잘 자라는 통성혐기성균이고, Gas를 생산하며 포자를 생성하지 않는 Gram음성의 간균이었다. 이것으로 보아 이균은 Enterobacteriacease의 Klebsiella oxytoca 로 동정했다. K-36에서 분리한 Sulfotransferase의 반응양식은 p-nitrophenylsulfate와 p-nitrophenol이 반응시간과 함께 동량씩 감소하여 반응 생성물인 phenylsulfate와 p-nitrophenol을 생성시켰으며 sulfatase 반응은 진행되지 않았다.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.966-970
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• 2010

본 연구의 대상지인 인천광역시, 부천시, 서울특별시, 김포시를 걸쳐서 흐르는 굴포천은 산업화와 도시화로 인한 생활하수 및 공장폐수의 유입, 느린 유속과 하천 복개 등과 같은 유입오염원과 하천 구조적 문제로 인하여 수질이 악화되어 왔다. 특히 하천변의 소규모 영세 공장, 중 상류에 형성된 대규모 공업단지, 지역개발에 따른 인구증가로 인한 생활하수 등은 굴포천의 주 오염원이다. 또한 직강화된 하도와 느린 유속 등 하천의 구조적인 문제점 등은 하천의 자정능력을 저하시키고 있어 현재 굴포천의 수질수준은 전국 최하위에 머물러 있다. 더욱이 입자상 오염물질의 퇴적으로 인하여 굴포천의 하상은 대부분 퇴적오니가 형성되어 있다. 이러한 퇴적오니는 다량의 유기 물질 및 중금속 등을 흡착하고 있고, 재용출에 의한 내부오염 가능성을 내포하고 있기 때문에 오염원이 제거된 후에도 계속적인 수질오염을 일으킬 수 있다(Alloway et al, 1988). 따라서 본 연구에서는 굴포천 본류 전 구간 및 유입지천에 대하여 수질 오염도와 오염부하량을 산정하였으며, 본류 하상 퇴적물의 오염도 및 퇴적물의 용출특성에 관한 조사를 수행하였다. 본 연구는 굴포천 본류 구간을 최상류(GP-1)부터 최하류(GP-7)구간까지 총 7개 구간으로 구분하여 실시하였으며 각 지점별 수질 및 퇴적물 오염도를 조사하였다. 또한 3개의 유입지천에 대하여 수질 오염도 및 오염부하량을 산정하였다. 굴포천 하상의 경우 최상류의 GP-1지점을 제외하고는 전 구간이 대부분 오염된 오니가 퇴적되어 있으며, 이러한 퇴적오니의 퇴적물 오염도를 분석해본 결과 상류부인 GP-1, GP-2와 유속이 비교적 빠른 GP-7지점에 비하여 나머지 지점들의 오염도가 매우 높은 것으로 나타났다. 이러한 하상퇴적물의 영양염류 용출특성을 알아보기 위하여 호기 및 혐기조건에서 용출실험을 실시한 결과 호기와 혐기 조건에서 T-N은 각각 34.84 $mg/m^2/day$, 66.93 $mg/m^2/day$의 용출속도를 보였고, T-P의 경우 호기 조건 시 5.33 $mg/m^2/day$, 혐기 조건 시 6.84 $mg/m^2/day$의 용출속도를 보임으로서 퇴적물 용출에 의한 내부오염의 가능성이 있음을 보였다.

• Korean Journal of Environmental Agriculture
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• v.22 no.1
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• pp.26-35
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• 2003

An investigation was carried out to evaluate the effects of pebble size on the small-scale sewage treatment apparatus by natural purification method that consisted of aerobic and anaerobic plot. pH and EC in both plots varied minimally regardless of pebble size. DO in aerobic plot increased as the pebble size decreased. That in the anaerobic plot was slightly less in comparison with that of the aerobic plot but varied minimally, $2.4{\sim}5.1\;mg/L$ regardless of pebble size. Under all experimental conditions, removals of BOD, COD and turbidity in anaerobic plot were more than 98, 91 and 98, 98% respectively. Removals of T-N and T-P increased as pebble size decreased. Under all experimental conditions, removals of T-N and T-P in anaerobic plot were about $45{\sim}59$ and $480{\sim}96%$, respectively. Judging from the above results, it should be considered that the optimum pebble size and pebble permeability in both plot was $2{\sim}4$ and $0.1{\sim}4\;mm$, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.3
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• pp.170-174
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• 2005

Barley plants growing in the wet paddy field easily encounter suboptimal oxygen concentration in the rhizosphere that causes molecular oxygen deficiency in root cells. The capacity of root cells to utilize energy sources is known to be positively related to resistance to hypoxia stress. This study was conducted to investigate effects of hypoxia on enzymes involved in the starch and sucrose metabolism. Barley seedlings at the third leaf stage were subjected to hypoxia (1 ppm dissolved oxygen) by purging the culture solution with nitrogen gas for up to seven days. The protein content was slightly decreased by hypoxia for 7 days. $\alpha-Amylase$ activities increased significantly in the root but not in the shoot after 3 to 7 days of hypoxia. $\beta-Amylase$ activities were not affected significantly in both tissues. Additionally, sucrose synthase activities were affected little in both tissues by 7 days of hypoxia. The results indicate that root cells activate break­down of polysaccharide reserves in response to an acute hypoxia to supply energy sources for fermentative glycolysis and cell wall fortification.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.436-440
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• 2016

본 연구에서는 농업용 저수지의 수질을 악화시키는 원인으로 판단되는 퇴적물의 현황을 파악하기 위하여 저수지의 퇴적물에 영향을 미칠 수 있는 물리성 및 오염원 특성에 따라 유형 분류를 실시하여 각 유형별 대상 저수지를 선정하여 현장 모니터링을 통해 기초자료를 확보하였고, 이를 국내외 자료 및 수질자료와 비교 분석을 통해 총체적인 오염도를 평가하였다. 연구 대상 저수지의 분류 기준은 저수지 퇴적물의 성상 및 특성에 영향을 미칠 수 있는 주요 요소인 저수지 오염원과 설치년도로 하였다. 이에 따라, 현장 답사 및 사전조사 결과를 토대로 가장 적합한 조사대상 저수지를 선별하였다. 최종적으로 선정된 연구 대상 저수지는 생활계의 인평(1960년대 이전), 업성 저수지(1960년대 이후)와 축산계의 이담(1960년대 이전), 공리 저수지(1960년대 이후)이다. 내부 오염 부하량이 수체에 미치는 영향을 평가하기 위해 실시한 용출량 실험 결과, 호기 조건의 경우에는 축산계의 T-P를 제외하고 생활계, 축산계 모두 용출이 일어나지 않는 것으로 조사되었다. 반면에 혐기 조건의 경우에는 생활계 보다는 축산계가, 1960년대 이후보다는 1960년대 이전에 축조된 저수지의 용출이 보다 활발한 것으로 나타났다. 조건별 용출량이 수체에 미치는 영향은 호기 조건에서 생활계 및 1960년대 이후의 경우 음의 값을 보여 수질이 개선되는 것으로 나타났다. 반면, 혐기 조건에서는 T-N의 경우 생활계와 1960년대 이후 저수지에서는 용출이 일어나지 않았으나 그 외의 항목에서는 모두 용출이 일어나는 것으로 나타났다. 특히 혐기조건은 T-P의 용출에 영향을 크게 미치는 것으로 나타났는데, 수질에 미치는 영향을 기여율로 환산할 경우 생활계에서 11%, 축산계에서 13.7%, 1960년대 이전에서 18.3%, 1960년대 이후에서 6.39% 영향을 미치는 것으로 나타났다.

• Korean Journal of Environmental Agriculture
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• v.25 no.1
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• pp.14-24
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• 2006

To develop small-scale sewage treatment apparatus for detached house of agricultural village, a small-scale sewage treatment apparatus by natural purification method that consisted of aerobic and anaerobic bed was constructed. To reduce the area of a sewage treatment apparatus, four different fitter media were used and each filter medium was coarse sand, broken stone, steel slag, and mixed fitter media (coarse sand : broken stone : steel slag = 1:1:1). The efficiency of sewage treatment according to the depth of aerobic and anaerobic bed and the volume ratio of aerobic to anaerobic bed were investigated in small-scale sewage treatment apparatus. The removal rate of pollutants according to the depth of aerobic and anaerobic bed in small-scale sewage treatment apparatus was high in the order of 50 cm < 70 cm < 90 cm. The removal rate of pollutants according to the ratio of aerobic to anaerobic bed in small-scale sewage treatment apparatus was high in the order of 1:1 < 1:2 $\fallingdotseq$ 1:3. Under the optimum conditions, removal rate of BOD, COD, SS, T-N and T-P were $98{\sim}99,\;95{\sim}97,\;99,\;65{\sim}66\;and\;96{\sim}99%$ respectively, in small-scale sewage treatment apparatus.