• 한국토양비료학회지
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• 제46권5호
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• pp.386-390
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• 2013

Recently, special attention has been given to acid rain and its problem to environment such as acid precipitation and air pollution in East Asia. In the present study, rainwater samples were collected from Apr to Nov in 2012. The samples were chemically characterized for the assessment of emission sources. Suwon and Yeoju regions, typical agricultural areas in South Korea, were chosen for study sites. Ion composition and cation-affected neutralization were determined to evaluate the contribution of cations to the acidity of rainwater. Ion and electrical conductivity between the measured and the estimated showed high correlation. The cations observed in Suwon and Yeoju were $Na^+$ > $NH_4{^+}$ > $K^+$ > $Ca^{2+}$ > $Mg^{2+}$ > $H^+$ and $Na^+$ > $K^+$ > $NH_4{^+}$ > $Ca^{2+}$ > $Mg^{2+}=H^+$, respectively. The anions of all sites were $SO{_4}^{2-}$ > $NO_3{^-}$ > $Cl^-$. While the amounts of sulfate, one of the major dissolved components of rainwater, were 77.6 and 75.6 ueq $L^{-1}$ in Suwon and Yeoju, the ones of NSS-$SO{_4}^{2-}$ (Non-Sea Salt sulfate) were 83 and 82% in Suwon and Yeoju, respectively. The comparison of observed pH values ($pH_{obs}$) with the theoretical pH values ($pH_{the}$) showed that the neutralization of rain water considerably went along during the study periods. The highest amounts of rainfall throughout the year in Suwon and Yeoju were 572.3 and 484.6 mm in July, and its corresponding nitrogen loadings in Suwon and Yeoju were 5.28 and 3.50 kg $ha^{-1}$, respectively. The major ion contents for crop growth with $SO{_4}^{2-}$, $Ca^{2+}$, $K^+$ and $Mg^{2+}$ were 51.7, 5.2, 11.8 and 1.8 kg $ha^{-1}$ in Suwon and 34.2, 4.0, 4.2 and 1.1 kg $ha^{-1}$ in Yeoju.

• 한국습지학회지
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• 제18권4호
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• pp.363-377
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• 2016

본 연구는 낙동강수계 오염도가 높은 금호강 및 남강 중권역의 지천들 가운데 수질측정망과 일정한 거리에 있고 오염도가 높은 지천들을 선정하여 각 지점의 오염부하량, 오염특성, 중점관리지천별 세부 유입되는 지천의 오염현황 및 중점 지류가 낙동강 본류에 미치는 영향 등을 살펴보았다. 그 결과, 금호강 및 남강의 대부분의 수질항목별 오염도는 유사하였으나, TN, Chl-a 및 SS는 금호강이 남강에 비해 약 20~120% 이상 높은 오염도를 보였다. 오염발생부하율(kg/day) 및 발생밀도($kg/day/km^2$)는 유량과 하천유하면적에 따라 하천 오염도 순위가 달랐으며, 이러한 영향은 남강에서 더 크게 차이가 발생하였다. 금호강 및 남강의 상세오염조사는 하천의 유로길이, 합류되는 소하천의 개수와 형태에 따라 상세지점을 2개에서 최대 9개까지 나누어 조사하였으며, 그 결과 달서천과 의령천의 오염도가 높게 나타났다. 이외에도, 달서천과 의령천의 본류오염 기여율이 약 10% 내외로 높게 나타났으며, 이는 주변공단, 생활거주지역 형태 및 크기, 농경지 경작 유 무 및 축사 존재 유 무에 따라 오염도 및 상 하류 오염형태가 다르기 때문으로 판단된다

• 상하수도학회지
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• 제24권2호
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• pp.195-202
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• 2010

The evaluation of organic matters and nutrients removal was investigated for the synthetic wastewater and the high strength of dairy wastewater. Two different systems were performed for this research. System A composing of a single RBC with tapered aeration was fed with the synthetic wastewater for 74 days with 173L/day of influent, 200% of internal return and 100% of sludge return for the period 1 and 2. The feed conditions were maintained 346L/day of influent, 50% of internal return and sludge return for the period 3. The dairy wastewater was introduced to evaluate treatment efficiency for system B composing of dual RBCs and tapered aeration tanks for 50 days of experimental run time, in which hydraulic rates were maintained at the constant ratios of 346L/day, 50% of internal return and 50% of sludge return. The spiral string media made of nylon fibre was attached by Bacillus sp. in RBC for both systems. The specific area of string media was $1.4m^2$/m and biomass was maintained at the concentrations of 23g/m. The synthetic wastewater was supplied by 1,800mg/L of glucose, 500mg/L of $NH_4Cl$, and 500mg/L of $KH_2PO_4$ to system A. The dairy wastewater was supplied to system B from dairy production plant. The average influent concentrations were 1,334mg/L of BOD, 2,014mg/L of CODcr, 160mg/L of T-N, and 12mg/L of T-P in system A. The average influent concentrations of parameters were 1,006 mg/L for BOD, 1,875mg/L for $COD_{cr}$, 51.6mg/L for T-N and 8.9mg/L for T-P in system B. Results indicated that removal efficiencies of BOD and $COD_{cr}$ were more than 90% however, the removal efficiency of T-N was 87%, and that of T-P was 82% for system A. Removal efficiencies were 98.5% of BOD, 91.3% of nitrogen and 89% of phosphorus for system B. The removal efficiencies of organic matters, T-N and T-P were higher in system B than in system A. The effluent quality issued by the stringent national legislations for the discharge of the high strength of dairy products wastewater can be improved using sequential RBCsand tapered aeration reactors rather than a single RBC and tapered aeration reactors with Bacillus sp.

• Ocean and Polar Research
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• 제27권3호
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• pp.251-263
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• 2005

In order to study changes in the marine ecosystem of the East China Sea derived by the global warming and construction of the Three Gorges Dam in the middle of the Changjiang, temperature, salinity, nutrients, and chlorophyll-a were studied intensively in the northern part of the East China Sea during the summer of 2003 and spring of 2004. According to the previous studies, the upwelling of the Kuroshio Current and the Changjiang resulted in a major inputs of nutrients in the East China Sea, but these two inputs may not contribute gently to a build up of nutrients in the northern East China Sea. In spring, relatively high concentrations of nitrates and phosphates were observed in the western part of the study area, which resulted from the supply of high concentrations of nutrients showing up in the surface waters as a result of vertical mixing from the ocean bottom. The concentrations of nitrates and phosphates observed in summer were lower than those in spring, since the surface waters were well stratified by the larger discharge of fresh water from the Changjiang in summer. The surface nitrate/phosphate ratios ranged from 1.3 to 16 in spring and from 1.1 to 15 in summer and were lower than the Redfield ratio of 16, indicating that the growth of phytoplankton is limited by nitrogen. This results are contrary to the previous results, in which the growth of phytoplankton was limited by phosphate in the East China Sea. The reason for this contrary result is that most nutrients in the surface waters are supplied by vertical mixing from the bottom waters with low nitrate/phosphate ratios, not directly influenced by the Changjiang with high nitrate/phosphate ratios. The depth-integrated chlorophyll observed in summer was similar to the previous results, but those measured in spring were almost twice as high as those found in previous results. The depth-integrated chlorophyll in spring was higher than that of summer, which results from high concentrations of nitrates and phosphates in the surface waters in spring due to active vertical mixing.

• 한국환경농학회지
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• 제17권4호
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• pp.329-334
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• 1998

본 연구에서는 축산농가에서 환경오염의 저감방안을 강구하기 위하여 축산폐수의 혐기성 처리수와 생활잡배수를 혼합하여 합병정화조와 3단 soil filter를 연계하여 처리한 결과, 다음과 같은 결론을 얻었다. 합병정화조에서 처리함에 있어서 합병정화조내 충전된 여상과 체류시간의 증가로 인한 미생물의 축적에 의하여 NRT $4{\sim}12$일에서 CODcr 제거효율은 $63.4{\sim}84.0%$이며 NH4+-N와 PO43--P는 각각 $3.9{\sim}5.4%$와 $18.3{\sim}29.0%$로써 HRT가 증가함에 따라 높은 효율을 나타내었다. 3단 soil filter에 의하여 재처리함에 있어서 표면적 부하율의 점진적인 증가에도 불구하고 여과, 흡착, 이온교환 및 토양 미생물의 작용으로 인하여 표면적 부하율이 증가함에 따라 CODcr, NH4+-N 및 PO43--P의 제거효율은 90% 이상을 나타내었다. 이상의 결과를 미루어볼 때, 오염부하량 감소 및 농업용수로의 재이용 측면에서 축산폐수의 합병정화조와 Soil filter에 의한 연계처리를 할 경우에 '96년부터 적용된 축산폐수의 방류수 수질기준에 적합한 것으로 나타났다.

• 수산해양기술연구
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• 제22권4호
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• pp.1-20
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• 1986

Physical, chemical and biological surveys on Nakdong River estuary were made from October, 1985 to September, 1986. 1. For all the seasons except summer, the sea surface temperature in northwest area of the line which linked from Seo Island to Jisim Island was I-2$^{\circ}$C lower than in southeast area, but in summer the sea surface temperature in northwest area was I-2$^{\circ}$C higher than in southeast area. On the contrary, bottom temperature of coastal area was 1$^{\circ}$C higher than that of oceanic area except winter. 2. Surface salinity in summer and fall has minimum value of 1. 9%0 and maximum value of 32.9%0. This large variation was caused by the runoff of the Nakdong River. Effect of less saline Nakdong River water in northwest area of the line which linked from Seo Island to Jisim Island was greater than in southeast area. A strong current rip always formed near this line. 3. The yellowish-green colored zone was observed in the Nakdong River estuary throughout the year by influence of river discharge. The characteristics of the water quality in the zone have shown that the water color was grade 7 by the Forel water-color meter, transparency was less than 4 m, and concentration of suspended solids was more than 5 mg/1. This water body was in the state of eutrophication in terms of chlorophyll-a and inorganic nitrogen concentration during summer season. 4. During the study period, total 276 taxa were identified. Most of them were diatoms and dinoflagellates which consisted of 97.5%. The component ratio of the above two groups was 84.4% and 13.1 % respectively. Diatoms were plentiful in December and dinoflagellates in July. Dominant species were Nitzschia seriata in October, Thalassiosira rotula in December, Skeletoncma costatum in April, and Nitzschia longissima in July. 5. A total of 47 zooplankton taxa was identified from the samples collected. Copepods were numerically the most important components of zooplankton communities in the study area. The domir:ant copepod species were Paracalanus parvus, Acartia clausi and Temora turbinata. Noctiluca scintillans was the next important component. The other zooplankton with minor abundance were Cladocera. Sagitta spp., Cnidaria, Mysidacea, Lucifer spp. and Amphipoda. 6. During the study period, fishes from 47 families and 87 species were sampled in th~ study area. The four most abundant fish species were Rep~mucen//'s valencicnnei, Leiognathus n~cha!is, Amblychaeturicllthys hexanema and Sardirel/a zun:zsi. The fish species of the secondary importance in abundance were Cynoglossus joyneri, Sillago sihama, Engra~lis japonicus, Encdrias nebulos'l, Acanthogobius flavimanus, Trichiurus lepturus, LiParis tanai/ai, Cynagloss//'s interruptus, Aj)ogon line:z!us, Thrissz la 1l.'1la!ensis, and Limanda yokohamac.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2006년도 추계학술발표회
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• pp.97-104
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• 2006

선박과 항만 터미널에 의한 오염에 대하여 항만 환경의 보호를 위해 강력한 규제지침을 적용해야한다. 불법적인 선박의 밸러스트수 교환으로 발생하고 연안의 항내에 들어와서 교환을 하면 식물과 동물의 외래종 침입하여 먹이 사슬을 파괴하는 원인이 된다. 질소가 풍부한 물의 교환은 미생물의 성장을 촉진시켜 연안에 적조를 유발시킨다. 또한 항만의 나쁜 영향을 미치는 것은 선박과 물동량을 수송하는 트럭에서 다량의 디젤 산화물을 대기로 배출한다. 국제해사기구 (International Maritime Organization: IMO) 에서는 선박에서 발생되는 오염물질 둥에 대한 규제강화를 위하여 최근 새로운 해사환경협약의 채택 및 발효를 강력히 추진하고 있다. 우리나라는 국제해사기구의 A 그룹 이사국으로서의 국제적인 위상과 해양환경 보호를 위하여 현재 발효되고 추진 중에 있는 협약들에 대한 연구와 대처를 효과적으로 하여야 한다. 이 논문은 해양관련 환경규제협약인 대기오염방지협약, 선박의 유해방오도료 사용규제협약, 밸러스트수 배출규제협약, 선박으로부터 오수에 의한 오염방지를 위한 협약 풍의 주요 현안을 파악하고 분석하여 이에 따른 대응책을 제시하고자 한다.

• 한국수산과학회지
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• 제35권1호
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• pp.86-96
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• 2002

1999년 3월부터 2001년 4월까지 섬진강하구역에서 염분경사에 따른 부유입자물질 (SPM), 엽록소 $\alpha$, 입자유기 탄소 (POC)와 질소 (PON) 그리고 입자유기규소 (PBSi)의 분포를 조사하였다. 조사 정점은 지리적 위치보다는 각 조사시마다 표층염분을 현장에서 측정하여 결정하였다. 섬진강으로부터 다량의 육수가 유입됨에도 불구하고 대부분의 조사시기에서 SPM의 농도는 20mg/L 이하로 낮아 섬진강을 통해 유입되는 육상기원의 SPM 공급은 낮은 것으로 판단된다. 1999년 11월의 5$\~$15psu (난초도로부터 10$\~$20km), 2000년 4월의 15$\~$25psu (10$\~$20km), 그리고 2000년 10월의 약1$\~$15psu (15$\~$20km) 염분구간에서는 엽록소 a농도가 약 8$\~$58$\mu$g/L로 매우 높았으며 POC, PON 및 PBSi의 농도도 매우 높았다. POM의 농도가 매우 높았던 염분역을 포함한 중간염분역에서의 POC와 엽록소 $\alpha$ 비가 비교적 낮아 POC의 대부분이 식물플랑크톤으로 구성되어 있음을 보여주고 있다. 반면, 초저염분역과 하구 입구에서는 POC와 엽록소 $\alpha$ 비가 상대적으로 높아 담수 및 저층으로부터의 detrital POC 공급이 있었음을 의미한다. 따라서 섬진강 하구수역에서의 비교적 낮은 SPM 농도와 중간염분역에서의 높은 엽록소 $\alpha$ 농도 및 낮은 POC와 엽록소 $\alpha$ 비는 식물플랑크톤 생산이 염분에 따른 POM의 분포를 조절하는 가장 중요한 요인임을 시사해 준다.

• 한국수산과학회지
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• 제34권4호
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• pp.348-354
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• 2001

This study was conducted to estimation of change characteristics for water quality by the dyke gate operation in the Keum River estuary. The estimation data made use of surveyed data in Keum River estuary by NERDI (National Fisheries Research and Development Institute) during $1990\~1999$. Shown to compare water quality changes at st. A and st. D in Figure 1, the concentrations of TSS, COD and nutrients at st. A were as high as about $2\~4$ times than those at st. D due to affection of fresh water discharge in the Keum River. The percentages of water quality change at surface water by dyke gate operation in the Keum River estuary were shown that TSS (Total Suspended Solid) was decrease to $56\%,\;47\%$ at st. A and D, and COD (Chemical Oxygen Demand) was increase to $68\%,\;71\%$ at st. A and D, respectively. The changes percentage of DIN (Dissolved Inorganic Nitrogen) by dyke gate operation in the Keum River estuary were increase high to $95\%$ at surface water and $7\sim30\%$ at bottom water, but those of DIP (Dissolved Inorganic Phosphorus) were increase to $2.8\sim8.6\%$ at surface water and $28\%$ at bottom water. The range of fluctuation for water quality at each station by dyke gate operation has shown that salinity and TSS are little better than before dyke gate operation, but COD show highly fluctuation. Also we studied estimation of characteristics of water quality change by the season, COD was increased except the summer, TSS was decreased to all season. DIN was increased to about $61\sim172.1\%$ for all season, but DIP was increased to the spring and decreased to the autumn, DIN enrichment in the estuary by dyke gate operation are interpreted to improvement of organic matter decomposition and nitrification by increasing the residence time and to increase nutrient flux in sediments due to decreasing dissolved oxygen and increasing a deposit matter.

• 한국재료학회지
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• 제11권8호
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• pp.671-678
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• 2001

$RuO_2$ 박막을 전극으로 하여 Pt/Ti/Si 기판 위에 $RuO_2$ /LiPON/$RuO_2$의 다층 구조로 이루어진 전고상의 박막형 마이크로 슈퍼캐패시터를 제작하였다. 전극용 $RuO_2$박막은 반응성 dc 마그네트론 스퍼터를 이용하여 $O_2$/[Ar+$O_2$]비를 증가시키며 성장시켰고, 비정질 LiPON 고체전해질 박막은 순수한 질소분위기 하에서 rf 스퍼터링으로 성장시켰다. 상온에서의 충-방전 측정을 통해 $RuO_2$ 박막의 미세구조에 따라 슈퍼캐패시터의 사이클 특성이 영향을 받는 것을 알 수 있었다. Glancing angle x-ray diffraction(GXRD)과 transmission electron microscopy (TEM) 분석을 통해 산소 유량의 증가가 $RuO_2$박막의 미세 구조의 영향을 주는 것을 알 수 있었고, X-ray photoelectron spectroscopy (XPS) 분석을 통해 산소 유량 비의 증가가 Ru과 산소간의 결합에도 영향을 줌을 알 수 있었다. 또한 사이클 후 슈퍼캐패시터의 TEM 및 AES depth profiling 분석을 통해, 충-방전 시 $RuO_2$와 LiPON과의 계면반응에 의해 형성된 계면 층이 사이클 특성에 영향을 줌을 알 수 있었다.