• 환경영향평가
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• 제16권5호
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• pp.341-350
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• 2007

Lake Youngrang is a lagoon whose effluent flows into the East Sea. Because two resort towns and two golf courses are situated at the lake basin, many tourists visit this area. Stormwater runoff surveys were carried out for the eight storm events from 2004 to 2005 in the eutrophic lake watershed to give a basic data for the diffuse pollution control of the lake. Dimensionless mass-volume curves indicating the distribution of pollutant mass vs. volume were used to analyze the first flush phenomenon. The mass-volume curves were fitted with a power function and polynomial equation curves. The regression analysis showed that the polynomial equation curves were better than the power function in representing the tendency of the first flush, and second degree polynomial equation curves indicated the strength of the first flush effectively.

• 한국물환경학회지
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• 제26권5호
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• pp.850-859
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• 2010

Structure and succession of zooplankton community studied by hydraulic and ecological characteristics targeting the five lakes in the Han river system from March to December 2008. Results separated by river-type lake and lake-type lake depending on the type of hydraulic, Paldang lake and Cheongpyeong lake were river-type lake, while Chungju lake, Hoengseong lake and Doam lake was lake-type lake. The Paldang lake was a eutrophic lake, zooplankton community density and species number were the most among the five lakes. Relative dominance of the rotifera was the largest and the yearly first dominant species was a small cladocera Bosmina longirostris. The Cheongpyeong lake was a mesotrophic-eutrophic lake, hydraulic characteristics and zooplankton community changes were similar the Paldang lake. Relative dominance of the cladocera was the largest and the yearly first dominant species was a small cladocera Bosmina longirostris. The Chungju lake was a oligotrophic-mesotrophic lake, zooplankton community density was the least among the five lakes. Relative dominance of the copepoda was the largest and the yearly first dominant species was a large cladocera Daphnia galeata. The Hoengseong lake was a oligotrophic-mesotrophic lake, relative dominance of the rotifera was the largest and the yearly first dominant species was a small cladocera Bosmina longirostris. The Doam lake was a mesotrophic-eutrophic lake, zooplankton community density showed dramatic difference at the investigation time. Relative dominance of the rotifera was the largest and the yearly first dominant species was the copepoda Nauplius.

• 한국해양바이오학회지
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• 제10권2호
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• pp.91-96
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• 2018

There are many eutrophic lakes by point and non-point pollution sources such as in dustrial waste water, domestic raw sewage, and mucks. The eutrophic lakes not only cause algal blooms but also destroy the ecosystem in the lakes due to high nutrient concentrations. The purpose of this study was to improve water quality in eutrophic lakes by cultivating microalgae using photobioreactors (PBRs) with selectively permeable mesh (SPM), supplying nutrients in the lake and inhibiting cell leakage by diffusion and water permeability. Chlorella vulgaris, was cultivated using PBRs with SPM installed in Inkyung Lake located in Inha university, Incheon, Korea. When cultivating C. vulgaris, $8.3g/m^2/day$ of average biomass productivity was obtained at 3 days. Furthermore, concentrations of total nitrogen and phosphorus were reduced by 35.7% and 84.2%, respectively, compared to initial condition and water quality in eutrophic lake was improved to oligotrophic environment. These results suggest that microalgal cultivation using PBRs with SPM in the lake could produce microalgal biomass as well as improve water quality by decreasing nutrient concentrations.

• Environmental Engineering Research
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• 제7권2호
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• pp.93-101
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• 2002

The seasonal patterns of dissolved organic matter (DOM) in Lake Kasumigaura, a shallow, eutrophic lake, and serveral DOM sources in its catchment area were investigated. DOM was fractionated using three resin adsorbents into classes: aquatic humic substances (AHS=humic acid+fulvic acid), hydrophobic neutrals (HoN), hydrophilic acids (HiA), bases (BaS) and hydrophilic neutrals (HiN). The DOM produced significantly different fraction distributions depending on the origin of sample. AHS and HiA prevailed over AHS in the lake while AHS and HiA existed at almost the same concentration levels in the rivers. AHS seems to be a more dominant component in rever water than lake water. The dominance of organic acids was also observed in the DOM sources: forest stream (FS), plowed field percolate (PFP), domestic sewage (DS) and sewage treatment plant effluent (STPE).

• 환경위생공학
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• 제12권3호
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• pp.31-39
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• 1997

The seasonal and spatial changes in dissolved organic carbon(DOC) in Lake Kasumigaura, a shallow and eutrophic lake, were analyzed from October 1992 to October 1995. The proportion of T-DOC was classified by labile(L-DOC) and refractory DOC(R-DOC) on the basis of long-term incubation, fractionated the molecular weight of T-DOC by ultrafiltration. The porewater DOC were measured at sedimental surface of the central basin in order to evaluate the DOC released from the sediment. The proportion of L-DOC and R-DOC were accounted for about 15% and 85% of T-DOC in the central basin, respectively. The molecular weight(MW) distribution occupied some 60% of the low and medium MW. The horizontal variation of T-DOC concentrations trended to higher in the central basin than in the inlet of influent rivers, because of contribution by autochthonous organic carbon loading. The seasonal variation of T-DOC showed to higher summer than winter in the inlet of influent, but at the central basin it fluctuated little seasonally. During the high increase of porewater DOC in 1994 evaluated the high release possibility from the sediment surface (10cm). The present study suggests that autochthonous organic carbon loading must be controlled for improving the water quality of the eutrophic lakes.

• 한국해양학회지
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• 제24권3호
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• pp.148-156
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• 1989

본 연구는 여러 수생생태계에서 유기물의 동적순환에 따른 부유성 박테리아와 부착성 박테리아의 그램염색(gram-stain) 특성을 알아보기 위한 일련의 시도로서 일본에서 두번째로 크며 부영양화가 상당히 진전된 가스미가우라 호수에서 1년간, 매주 실시했다. 이 전형적인 부영양형(eutrophic) 수생생태계의 박테리아군집의 그램염색 특성은 중영양형(mesotrophic) 환경과 같이 유기물의 유입에 따라 변화함을 보여준다. 그램음성(negative) 박테리아군집은 부유성 박테리아군집이 약 57%, 부착성 박테리아군집이 약 53%이며, 두 군집의 통계분석은 서로 다른 특성을 보여준다. 부착성 박테리아군집은 그램 양성, 음성 모두 쇄설성 유기물 형성과 분해에 영향을 미친다. 또한 그램 음성 부유박테리아는 특히 용존 유기물의 동적순환에 관여한다.

• 상하수도학회지
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• 제18권2호
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• pp.247-253
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• 2004

Major species of Lake Deganuma has varied depending on the season. Namely, there are Micractinium pusillum, chlorella., Scenedesmus sp. shown up in spring season, Microcystis aeruginosa, Microcystis wesenbergii, Anabena spiroides in summer and autumn season and Cyclostephanos invisitatus, Diatoma in winter season in the Lake. As the number of plankton increased, the zeta potential on their surface of them decreased. For this reason, they were dispersed in the lake though the population increased. Zeta potential of M. aeruginosa showed -20mV when their outer size got smaller. As for coagulant dosing in DAF, large amount of coagulant was effective to get lots of sludge during water treatment.

• 생태와환경
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• 제46권2호
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• pp.225-233
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• 2013

부영양호 신갈지의 수질개선을 위하여 이미 개발된 천연물질 혼합제(PMC)의 수질개선능(WQI)에 수온변화가 어떠한 영향을 미치는지 현장실험을 실시하였다. 실험결과 식물플랑크톤, BOD, 총인 등은 $20^{\circ}C$ 이하에서는 70% WQI 이상을 보였으나 $25^{\circ}C$ 이상에서는 40% WQI 이하로 오히려 감소하였다. 한편 수온의 증가에 따라 남조류에 대해서는 WQI는 감소하였고, 규조류는 수온변화에 상관없이 90% 이상 높은 WQI를 나타냈으며, 박테리아와 총 질소는 수온과 상관없이 매우 낮은 WQI를 보였다. 이상의 결과들은 PMC의 수질개선능이 수온과 밀접한 관계를 가지며, $25^{\circ}C$ 이상의 고온기에 Microcystis aeruginosa가 우점하는 남조대발생보다 겨울철 저온기에 우점하는 규조류에 더 효과적일 것으로 판단되었다.

• Journal of Plant Biology
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• 제14권1호
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• pp.15-23
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• 1971

The productivity of summer phytoplankton communities in Lake Hwajinpo, Lake Yongrang and Lake Changja were studied by measuring vertical variation of chlorophyll a amounts. The author also classified the lake types on the basis of the amount of chlorophyll in the lake water. And in Lake Changja, the seasonal changes of stratification of chlorophyll were studies. In Lake Hwajinpo, the productive structure of the phytoplankton community in summer was found to be L-shaped and of the mesotrophic type. In Lake Yongrang, the productive structure of the phytoplankton community in summer was alo L-shaped and of the mesotrophic type. And maximum chlorophyll layer was near the lake bottom below the compensation depth. In Lake Changja, the structure of phytoplankton community in summer was reversed L-shaped and of the eutrophic type, with the maximum chlorophyll layer just below the surface. The vertical distribution of chlorophyll amounts as a measure of the productive structure almost always formed a stratum distribution except in September and sometimes in May, in Lake Changja. In September homogeneous distribution was observed.

• 환경생물
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• 제22권1호
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• pp.227-232
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• 2004

Hydrological and biological studies on ecosystems of the lakes 'etang de Berre' and 'etang de Vaime', the four rivers flowing into these lakes, and the Mediterranean Sea are carried out during the whole two-year period. The phytoplankton population of the lakes 'etang de Berre' and 'etang de Vaine' is larger than that of the seawater or freshwater populations of four neighbouring rivers. This is due to the increasing nutriments such as phosphate, nitrate, and silicate flowing into the lakes from the four rivers. The superfluous phytoplanktons in the lakes flow into the Mediterranean Sea via the Caronte Canal. Phytoplanktons multiplicated by phosphate of lake 'etang de Berre' can produce 10,160 tons of assimilated carbon per year, and those multiplicated by nitrate produce 18,450 tons of assimilated carbon per year. According to Steeman Nielsen's primary production estimation, phytoplanktons produce about 45,000 tons of carbon per year through assimilation in lake'4tang de Berre' and 10,000 tons of carbon per year in lake 'etang de Vaime'. The amount of carbon produced by phytoplanktons and the amount of phosphate, and nitrate are different according to the sea, river, and estuary.