• Journal of the Korean Society of Urban Environment
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• v.18 no.4
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• pp.455-463
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• 2018

This study was carried out to assess the distribution and pollution level of organic matters and nutrients in surface sediments of the Yeongsan River Basin. The surface sediments were collected from the mainstream (12) and tributaries sites (4) for two years from 2015 to 2016, and the particle sizes, organic matters (Ignition Loss, COD, TOC) and nutrients (TN, TP, SRP) were analyzed. The distribution of particle sizes was dominated by sand in the upstream sites (MS1-MS7) and by silt loam in the downstream sites (MS8-MS12), but MS3 and MS6, located slightly upstream of the two weirs, were found to be mostly loamy sand and silt loam, respectively. As a results of the correlation assessment, the organic matters (IL, COD, TOC) were strongly correlated with particle sizes, while the nutrients (TP, SRP) were weak except for TN. The concentrations of organic matter and nutrient were higher at the downstream and the sites nearby the two weirs (MS3, MS6). In particular, the TP concentration at the MS3 site sampled in the second half period of the years was higher than that in the first half periods. Comparing of sediments criteria, the organic matters and nutrients were evaluated to have almost no toxic effects at all sites.

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.567-575
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• 2018

The soil physical quality is a core factor in achieving two of sustainable agriculture's goals: productivity and environment. The purpose of this study was to assess changes in soil physical properties for nearly a decade through periodic monitoring of three cultivation types: upland, orchard, and paddy. Field surveys and lab analysis were conducted to determine the soils physical properties after every 4 years; upland (2009, 2013, and 2017), orchard (2010 and 2014), and paddy (2011 and 2015). In each year soil samples from 162-338 sites were collected. The bulk density of upland subsoil decreased from $1.53Mg\;m^{-3}$ to $1.50Mg\;m^{-3}$ while the plowing depth and subsoil organic matter increased from 13.7 cm to 19.5 cm and from $12.6g\;kg^{-1}$ to $18.3g\;kg^{-1}$ respectively during the period 2009-2017. Plowing depth for orchard increased from 16.7 cm to 18.9 cm. However, organic matter content decreased from $15.9g\;kg^{-1}$ to $15.4g\;kg^{-1}$ during the 2010-2014 period. For paddy, plowing depth and subsoil organic matter decreased from 17.5 cm to 16.7 cm and from $17.5g\;kg^{-1}$ to $15.8g\;kg^{-1}$ respectively. The subsoil bulk density increased from $1.47Mg\;m^{-3}$ to $1.52Mg\;m^{-3}$ from 2011-2015. Excess ratio for soil physical standards increased from 16% to 22% in orchard, 56% to 62% in paddy, and decreased from 41% to 29% in upland. The overall soil physical quality had been ameliorated for upland, but degraded for paddy. Improved tillage practices and application of appropriate organic matter is necessary to enhance the quality of soils, especially in the paddy field.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1991.11a
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• pp.10-13
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• 1991

• Korean Journal of Ecology and Environment
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• v.54 no.4
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• pp.346-362
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• 2021

A sediment control dam is an artificial structure built to prolong sedimentation in the main dam by reducing the inflow of suspended solids. These dams can affect changes in dissolved organic matter (DOM) in the water body by changing the river flow regime. The main DOM component for Yeongju Dam sediment control of the Naeseongcheon River was analyzed through 3D excitation-emission matrix (EEM) and parallel factor (PARAFAC) analyses. As a result, four humic-like components (C1~C3, C5), and three proteins, tryptophan-like components (C2, C6~C7) were detected. Among DOM components, humic-like components (autochthonous: C1, allochthonous: C2~C3) were found to be dominant during the sampling period. The total amount of DOM components and the composition ratio of each component did not show a difference for each depth according to the amount of available light (100%, 12%, and 1%). Throughout the study period, the allochthonous organic matter was continuously decomposing and converting into autochthonous organic matter; the DOM indices (fluorescence index, humification index, and freshness index) indicated the dominance of autochthonous organic matter in the river. Considering the relative abundance of cyanobacteria and that the number of bacteria cells and rotifers increased as autochthonous organic matter increased, it was suggested that the algal bloom and consequent activation of the microbial food web was affected by the composition of DOM in the water body. Research on DOM characteristics is important not only for water quality management but also for understanding the cycling of matter through microbial food web activity.

• Journal of Animal Environmental Science
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• v.13 no.2
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• pp.113-120
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• 2007

This study was conducted to measure Nitrogen(N), Phosphate($P_2O_5$), Potassium ($K_2O$), Organic matter(OM) and Moisture content of liquid pig manure by Near Infrared Spectroscopy(NIRS) and to develop an alternative and analytical instrument which are used for measurement of N, $P_2O_5$, $K_2O$, OM, and Moisture contents for liquid pig manure. The liquid pig manure sample's transmittance spectra were measured with a NIRS in the wavelength range of 400 to 2,500 nm. Multiple linear regression and partial least square regression were used for calibrations. The correlation coefficient(RSQ) and standard error of calibration(SEC) obtained for nitrogen were 0.9190 and 2.1649, respectively. The RSQ for phosphate, potassium, organic matter and moisture contents were 0.9749, 0.5046, 0.9883 and 0.9777, and the SEC were 0.5019, 1.9252, 0.1180 and 0.0789, respectively. These results are indications of the rapid determination of components of liquid pig manure through the NIR analysis. The simple analytical instrument for liquid pig manure consisted of a tungsten halogen lamp for light source, a sample holder, a quartz cell, a SM 301 spectrometer for spectrum analyzer, a power supply, an electronics, a computer and a software. Results showed that the simple analytical instrument that was developed can approximately predict the phosphate, organic matter and moisture content of the liquid pig manure when compared to the analysis taken by NIRS. The low predictability value of potassium however, needs further investigation. Generally, the experiment proved that the simple analytical instrument was reliable, feasible and practical for analyzing liquid pig manure.

• Journal of the Korean Chemical Society
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• v.30 no.5
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• pp.423-432
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• 1986

Atomic absorption spectrophotometric (AAS) determination of hexavalent chromium [Cr(VI)] in a waste water was studied. Cr(VI) was extracted with p-xylene from the wastewater, in the way of ion pair formation with anion exchanger aliquat-336(tri-caprylmethyl ammonium chloride). 100ml waste water, after organic materials were extracted out with toluene, was acidified with conc. HCl adjusting the medium to pH 0.5 and 20ml of p-xylene containing 0.01M aliguat-336 was used to extract Cr(VI) from the acidified solution. The absorbance of chromium was measured with air-acetylene flame at 357.9nm. Standard addition method was used in the determining concentration of Cr(VI) extracted. No interference has been found in the extraction of Cr(VI) by the Al(III), Fe(III) and Cr(III) ion presented. However, Fe(II) decreased the absorbance of Cr(VI), due to the fact Fe(II) reduces Cr(VI) to Cr(III). The contained organic material was removed prior to extracting process, since it may reduced the absorbance of Cr(VI). The recovery of added Cr(VI) was over 96%, which seems to be promising and the relative standard deviation was 3.95%

• Journal of Wetlands Research
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• v.16 no.4
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• pp.423-431
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• 2014

Supply of rural community sewage treatment plant (RCSTP) is need for protect of water quality like water source and development of agriculture areas. In this study conducted analysis on characteristics of RCSTP sewage and treatment efficiency of installed treatment process using operation results of RCSTP in an-dong area. high organic matter and nutrient were contained in RCSTP sewage of an-dong than urban area. RCSTP treatment process in an-dong was shown stable treatment efficiency. But nutrient treatment efficiency was shown more sensitive result about SRT and F/M ratio than organic matter treatment efficiency. And RCSTP treatment process in an-dong was shown higher treatment efficiency than other treatment proces like $A^2/O$, SBR and media. Thus, this process is effective treatment process for application of RCSTP.

• Applied Chemistry for Engineering
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• v.16 no.2
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• pp.180-186
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• 2005

This paper discusses the development of mixtures for silica fume as a stabilization/solidification agent and a binder for industrial wastewater residue containing organic and heavy metal contaminants. The UCS (unconfined compressive strength) gradually increased to 66.7% as the silica fume content increased to 15%. The leaching of TOC (total organic carbon) and chromium decreased as more OPC (Ordinary Portland Cement) was substituted with the silica fume. When a mixture had 5% silica fume, it retained about 85% TOC, and chromium leached out 0.76 mg-Cr/g-Cr in acidic solution. Also, microstructural studies of the solidified analysis showed that the silica fume caused an inhibition to the ettringite formation which did not contrilbute to setting but coated the cement particles and retarded the setting reactions. The results indicated that the incorporation of silica fume into the cement matrix minimized the detrimental effects of organic materials on the cement hydration reaction and the contaminant leachability.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.424-424
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• 2019

수질오염 저감을 위한 유기물질의 처리를 위해 생물학적 처리에 중점을 둔 하 폐수 처리시설의 증가에 따라 BOD로 대표되는 생분해성 유기물질은 꾸준히 감소하였으나, COD농도의 경우 뚜렷한 감소를 보이지 않고 있다. 유기물질 중 특히 난분해성 물질의 증가는 상수원으로 사용되는 하천의 경우 조류 증식 등을 유발하고 여과공정에 영향을 미쳐 상수처리의 효율을 떨어뜨리는 등의 환경적인 문제를 야기할 수 있다. 기존 BOD, COD로 대표되는 유기물질의 경우 각 유기물질별 상관관계 및 유출특성 등에 대한 연구는 많이 이루어졌으나, 난분해성 물질에 대한 조사는 상대적으로 미진한 실정이다. 특히 동진강수계는 '새만금 제2단계 수질개선종합대책' 등 장기적인 수질개선 대책들이 추진되면서 하천의 BOD5 및 TP는 감소추세를 보이고 있으나, COD는 개선되지 않고 증가하는 추세를 보이고 있다. 동진강의 말단부의 경우 COD/BOD5의 비율이 지속적으로 증가하는 추세를 보이고 있어 상대적으로 난분해성 유기물질에 대한 관리의 중요성이 대두되고 있다. 이러한 COD 및 COD/BOD5의 증가 추세는 국내 4대강에서 전반적으로 나타나고 있는 추세로서, 정부는 2013년부터 하천 및 호소의 생활환경기준에 TOC 항목을 도입하여 2016년부터 호소환경기준의 대표항목을 COD에서 TOC로 대체하였으며, 폐수배출시설에 대해서도 점차적으로 확대 적용할 계획으로, 난분해성물질을 포함하는 총유기물질 관리를 위해서 수질 및 수생태계 환경기준에서 유기물질에 대한 환경기준을 BOD5와 COD에서 TOC로 변경하는 정책을 추진 중에 있다. 본 연구에서는 동진강 유역의 본류 및 지류에서 TOC등 유기물질의 시공간적인 분포와 오염원별 배출특성을 현장조사를 통해 조사 분석하였다. 조사 시기는 건기시, 강우시로 구분하여 수행하였으며 조사항목은 일반수질항목, 유기물질 항목, 유기물질 성상 분석 등에 대하여 수행하였다. 난분해성물질 관리를 위한 기초자료확보를 통하여 새만금호의 수질개선 및 목표수질 달성에 기여 할 것으로 판단된다.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.888-892
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• 2004

농지, 임야지역에서의 강우유출수 수질의 파악은 수자원 수질관리에 있어서 바탕수질(Background water quality)이기 때문에 물관리에 있어 매우 중요한다. 본 연구는 농지와 임야가 혼합된 도시외곽지역에서 강우시에 발생하는 강우유출수의 수질 및 오염부하량에 대하여 유역특성이 다른 두 지역에서 분석을 실시하였다. 연구 대상 유역은 임야와 농경지가 주를 이루는 지역으로 농지의 비율이 자자 $0.4\%$와 $35.9\%$인 유역이다. 측정은 건기에서부터 강우기 때까지 각 유역 당 10개의 강우 사상에 대하여 실시하였다. 측정 대상 항목으로는 pH, SS, TCOD, SCOD, BOD, TP, TN, $NH_3-N$, $NO_3-N$, $PO_4-P$, Total coliform, Escherchia Coli를 측정하였고, pollutograph, loadgraph을 작성하였다. 분석 결과 농지의 비율이 큰 유역에서 발생하는 오염부하량이 모든 수질 항목에서 높게 나타났으며, SS, 유기물, 미생물 항목에서 초기강우세척철상(first flush)을 보이고 있었다. 또한 측정 자료에 내한 동계분석결과 SS항목과 유기물 항목은 높은 상관관계를 나타내고 있었으며, 강우에 따른 오염부하량은 누승함수, 2차함수의 형태로 증가하였다.