• 한국환경과학회지
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• 제31권5호
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• pp.431-445
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• 2022

The Gwangju Stream is a major tributary of the Yeongsan River. To maintain environmental and ecological functions in the stream, the flow is secured by natural water from the Mudeung Mountain as well as waters discharged from Lake Juam and the Gwangju sewage treatment plants. A substantial amount of water is supplied into the upper reaches of Gwangju Stream from Lake Juam. To examine the ecological effects of the water input from Lake Juam on the Gwangju Stream, a field survey of phytoplankton community species and an evaluation of water properties was conducted at five stations, from station GJ1 before the inflow to station GJ5 in the lower region. Nutrient levels decreased in the vicinity of the Lake Juam inflow, suggesting that this water inflow can contribute to the reduction of eutrophication in the stream. The phytoplankton community was mainly composed of Bacillariophyceae, Chlorophyceae, and Cyanophyceae, and the community structure was similar to that of the other study sites located near the water inflow regions. The inflow of water from Lake Juam can affect water quality and the phytoplankton community over a limited area, reducing eutrophication and increasing water flow in the Gwangju Stream.

• 환경영향평가
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• 제14권5호
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• pp.255-262
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• 2005

In summer and early autumn, eutrophication occurs occasionally in many reservoirs. Lakeside macrophyte which is one of internal pollutants effects on water quality when it is submerged during water surface is rising after rainy season. This study include examination of pollutant load, species of plant, community structure and productivity of macrophyte in unit area at lakeside. The result of this research will be used as a guideline of water quality management on reservoir through assessing water quality effect of submerged plant. The areal distribution, composition of species and submerged area of macrophyte changes according to rainfall pattern every year, so it is difficult to calculate nutrient load annually from submerged macrophyte. In this study, the nutrient load from submerged macrophyte assess from Daecheong and Juam reservoir in 2001. TN and TP load of submerged macrophyte shows 0.043% and 0.069%, respectively, of annual discharge load on Daecheong watershed. At lake Juam, TN and TP shows 0.64% and 1.28% load, respectively. The reason that nutrient load of lake Juam is greater than that of lake Daecheong is that macrophyte distribution area of lake Juam is 5 times greater than that of lake Daecheong. Total nutrient load of lake Daecheong is 3 times greater than that of lake Juam.

• 생태와환경
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• 제40권3호
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• pp.419-430
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• 2007

본 연구는 주암호, 동복호, 영산호 세 호소의 이화학적 인자, 식물플랑크톤 생체량(Chl ${\alpha}$) 및 일차생산력을 조사하기 위하여 2004년 4월부터 2006년 3월까지 총 8회에 걸쳐 계절별로 실시하였다. 소형식물플랑크톤이 우점(>60%)한 동복호의 식물플랑크톤 생체량은 상류에서 2004년 4월에 높았지만 하류에서는 2004년 6월에 높은 분포를 나타내었다. 주암호에서 식물플랑크톤 생체량이 높았던 2004련 4월에 미소형식물플랑크톤의 기여율이 높았다. 영산호는 8월 (2004, 2005)에 높은 생체량을 보였는데 이 시기 미소형식물플랑크톤의 기여율이 높았다. 일차생산력은 동복호, 영산호, 주암호 순으로 높게 분포되었다. 단순 회귀 분석결과, 동복호에서 젠체식물플랑크톤, 소형식물플랑크톤과 일차생산력은 투명도와 상관성을 보였다. 주암호에서는 하류에서 크기별 식물플랑크톤과 $PO_4^{3-}$가 상관성을 보였고 일차생산력은 수온, TN과 높은 상관성을 보였다. 영산호 상, 하류에서 식물플랑크톤은 TN/TP와 음의 상관성을 보였고 일차생산력은 상류에서 높은 상관성을 보였으나 하류에서는 탁도와 높은 상관성을 보였다. 주암호와 동복호는 기타 환경 인자와의 단순회귀분석결과로부터 인과 질소 관리의 필요성이 제기된다. 영산호는 부유물질을 관리할 필요성이 있고 하류의 높은 일차생산력으로 보아 식물플랑크톤의 내부생산 기여율에 대한 추가적인 조사를 통한 저감방안 마련도 필요한 것으로 사료된다.

• 한국물환경학회지
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• 제29권3호
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• pp.317-328
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• 2013

The purpose of this study was to investigate the change of phytoplankton fluctuation and long term of water quality of Lake Juam and to evaluate the relationship between phytoplankton pattern and environmental factors data. Correlation and factor analyses were employed to identify key environmental factors affecting phytoplankton dynamics. Of 18 parameters, pH, temperature, COD, BOD and T-P were highly correlated with Chl-a. Phytoplankton data showed that cyanobacteria were dominant, and more than 60% of total algae density. Also Lake Juam received a lot of influence of the Asian monsoon climate. This study presents necessity of multivariate statistic techniques for evaluation of Lake Juam complex data set with a view to get better information data and effective management of water source.

• 생태와환경
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• 제39권3호통권117호
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• pp.296-309
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• 2006

조사 시기 동안 (2000~2004년) 주암호와 동복호에서는 겨울을 제외한 시기에 표층과 저층의 수온차이로 인해성층화가 발생하였지만 영산호에서는 나타나지 않았다. 투명도는 주암호>동복호>영산호 순으로 영산호에서 낮은 투명도를 보였으며 주암호와 동복호에서는 식물플랑크톤의 생물량이 높게 나타나는 가을 저층에는 저산소상태로 수질 악화를 나타내었다. 암모니아, 질산염, 인산염 TN, TP는 주암호와 동복호에 비해 영산호에서 높게 나타났으나 클로로필 a는 평균적으로 동복호에서 높았으며 영산호에서 낮았다. 3개호소의 여름, 가을 연평균 영양상태는 평균적으로 영산호>동복호>주암호 순으로 영산호에서 높았다. 주암호와 동복호에서는 TSI (CHL)>TSI (SD)>TSI (TP) 순으로 나타나 조류성장에 있어 인산염이 제한영양염으로 작용할 가능성을 나타내었으며 영산호에서는 TSI (TP)>TSI (SD)>TSI (CHL) 순으로 나타났다. 영산호에서는 인산염에 의한 제한보다는 탁도 즉 광량에 의한 제한이 식물플랑크톤의 성장에 영향을 미치는 것으로 판단된다. 주암호는 빈, 중영양을 보였으며, 동복호에서는 중, 부영양을 영산호에서는 부, 과영양을 보였다.

• 환경영향평가
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• 제8권4호
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• pp.37-45
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• 1999

Juam Lake is a major water resource for the industrial and agricultural activities as well as for the resident life of Kwangju and Chonnam regions. However, the water quality of the lake is getting worse due to a large quantity of pollutant inflowing to the lake. The excessive growth of algae by the overfertilization may result in water treatment problems and also the interference with desirable water uses of navigation, aesthetics, recreation and fish maintenance. Therefore, the purpose of this study is to analyze algal species and movements in Juam Lake in order to use as basic data in making the countermeasure to achieve the water quality goal of the lake. The results of the analysis show that (1) the predominant species of algae are Microcystis aeruginosa, Anabaena affinis, Melosira granulata, Synedra acus, and Coelastrum cambricum, (2) their groups are changed in order of diatoms, green algae, and blue-green algae with the lapse of time, and (3) the distance of the vertical movements of algae for 24 hours is about 2m.

• 한국농공학회논문집
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• 제47권3호
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• pp.77-86
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• 2005

A monitoring study has been conducted to identify hydrologic conditions, water quality and nutrient loading characteristics of small watershed in Juam Lake. Climate data of the watershed were collected; flow rate was measured and water quality sampling was conducted at the watershed outlet for this study. Water quality data revealed that T-P concentrations meet I grade of lake water quality standard during non-storm period, but degraded up to II-III grade of lake water quality standard during storm period. The observed T-N concentrations always exceeded lake water quality standard. Therefore, T-P was identified as limiting chemical constituent for eutrophication of Juam Lake. T-P concentration of non-storm period also revealed that point source pollution is not serious in the watershed. Three year monitoring results showed that the observed T-N losses were $10.85\~18.88$ kg/ha and T-P losses were $0.028\~0.323$ kg/ha during six month (Mar. - Oct.), respectively. Major portion of runoff amount discharged by a few storm events a year and nutrient load showed apparent seasonal variation. Huge runoff amounts were generated by intense storms, which make application of water treatment or detention facilities ineffective. Monitoring results confirmed that water quality improvement by abating nonpoint source pollution in rural watershed of monsoon climate should be focused on source control. T-P losses from paddy field seemed to consist of significant amount of total load from study watershed. Therefore, management of drainage from paddy field is considered to be important for preventing algal blooming problem in Juam Lake.

• 환경위생공학
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• 제21권4호
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• pp.39-48
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• 2006

In Juam basin, the ratio of non-point pollution source among pollutant loading of basin was significantly high, since the utilization level of land was high. In addition, the most pollutants were not treated and flowed out. In this study, the correlation between non-point source pollutants from the forest area and increasing algae was investigated. 1. Chl-a concentration flowed out to runoff from forest area and stream water was low as $0.1{\sim}20.3{\mu}g/{\ell}$ and $0.1{\sim}9.3{\mu}g/{\ell}$, respectively, and chl-a concentration ($0.1{\sim}28.5{\mu}g/{\ell}$) of branch stream was higher $5{\sim}7$ times than that of runoff from forest area. 2. In correlation between runoff from forest area and Juam lake water, annual chl-a concentration of area front Juam dam was higher twice than forest area. 3. In runoff from forest area within Juam basin, flagellate, green, diatom and blue algae occupied $33.0{\sim}41.7%$, $22.2{\sim}30.8%$, $17.3{\sim}22.5%$ and $13.7{\sim}17.6%$, respectively. 4. In runoff from forest area, both green and diatom algae were maintained constantly irrespectively of season, and flagellate algae dominated since August. 5. In characteristics by forest tree types, four types algae were inhabited in mixed forest, and flagellate algae were higher in conifer and broadleaf forest than in other area. And green algae in herbaceous forest were higher than other area.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.631-634
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• 2003

A subwatershed within the Lake Juam was monitored to identify hydrologic and water quality characteristics. Rainfall record was collected and flow rate measurement and water quality sampling were conducted periodically at the watershed outlet. Water quality of storm period was worse than that of base flow period. Nutrient loading from the watershed was governed by only a few storms during study period. Nonpoint source pollution was identified major problem for water quality management in Juam Lake.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2002년도 학술발표회 발표논문집
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• pp.433-436
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• 2002

A subwatershed within Juam Lake was monitored to identify hydrologic and water quality characteristics. Rainfall record was collected and flow rate measurement and water quality sampling were conducted periodically at the watershed outlet. Hydrologic response and pollutant load characteristics were analyzed based on observed data.