• 해양환경안전학회지
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• 제3권S1호
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• pp.77-90
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• 1997

the observations in situ and the seawater analyses were conducted in July and August, 1996 for the purpose of evaluating the characteristics of seawater quality centered on eutrophication in Mokpo harbour. By applying the OECD standards of trophic classification to the parameters such as secchi depth, total inorganic nitrogen, phosphate phosphorus and chlorophyll-a, the trophic level of seawater in Mokpo harbour was evaluated to be in eutrophic state in summer. By the estimation of pollution index with relation to eutrophication, the seawater quality of Mokpo harbour was evaluated to be under the regular grades and this evaluation was found to be different from the results of evaluation obtained by the environmental index of single parameter, chemical oxygen demand. By the estimation of eutrophication index, the seawaters of Mokpo harbour were shown to have the high potentiality of red tide occurrence.

• 한국환경과학회지
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• 제8권2호
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• pp.155-160
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• 1999

To investigate the water quality characteristics and eutrophication of the Keum River, survey were conducted on samples collected from 6 stations in Aug. and Oct. in 1995 and Jan. and May in 1996. The results were summarized as follows ; Concentration of pollutants were in the range of 1.74~6.35(mean 3.81)mg/$\ell$for BOD and 1.98~8.21(5.14)mg/$\ell$for COD and 1.46~51.94(18.52)g/$\ell$for TSS. Water quality were evaluate to be 2~3 grade of station 1 and other stations were 3~4 grade of water quality criteria. The concentration of nutrients were in the range of 55.2~735.3(309.3)$\mu\textrm{g}$-at/$\ell$for Dissolved inorganic nitrogen(DIN) and 0.06~6.03(2.80)$\mu\textrm{g}$-at/$\ell$ for dissolved inorganic phosphate(DIP). Nutrient concentrations in Keum River were usually high and the DIN/DIP ratio ranged from 72 to 2648. The concentration of chlorophyll-a was in the range of 1.1~143.7(44.3)mg/㎥. Chlorophyll-a concentration were high 10mg/㎥ except station 1, which is the value of eutrophication criteria by EPA. Correlations between nutrients and chlorophlly-a were not significant. According to eutrophication evaluation, Keum river was equivalent to the eutrophic state.

• 한국환경과학회지
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• 제16권3호
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• pp.357-367
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• 2007

Recently, eutrophication or lake and reservoir has become serious problem to man who want use that water for several purpose. In order to solve the eutrophication problem, the trophic state of that eutrophic lake and reservoir should be measured properly. For the purpose of this, various method to indicate the trophic state of lake and reservoir was developed by many researchers. This research was conducted to evaluate characteristics and eutrophication of water qualitymfor small scale reservoir in Kunsan. On-site investigation to 5 reservoirs and laboratory experiment were carried out during four seasons from November, 2003 to July, 2004. Twelve items measured field ana a laboratory. Measured data was analyzed to quantitative method by multivariate approach and eutrophication index. The result is summarized as following. 1) Showing the characteristics of water quality for reservoir in Kunsan, Okgu reservoir and Oknua reservoir was exceeded 4 grades of agricultural water standard in TP, TN and COD. This means that eutrophication was gone much, therefore, water-purity control of reservoir need. While, Mije reservoir that is used to Kunsan citizens' recreation was good in water quality. But, water quality exceeded 4 grades of agricultural Dater standard sometimes. 2) As a results of correlation analysis between variables of water qualify, Interrelation between variables which is connected with eutrophication was expressed good relationship as above 6.000 in correlation coefficients. The correlation coefficient(r) between COD and chlorophyll-a, total phosphorus and chlorophyll-a, total nitrogen and chlorophyll-a were 0.750, 0.720 and 0.600 respectively. Therefore, Change of water quality can grasp according to eutrophication progress degree. 3) If do evaluate to eutrophication by quantitative method which is proposed by OECD, US-EPA and Forsberg & Ryding, in the case of chlorophyll a, Okgu, Oknua and Daewi reservoir was eutrophic state and Mije and Geumgul reservoir was mesotrophic state. But, estimation by TN and TP showed highly eutrophic state (hypereutrophic) in all reservoirs. 4) If do evaluate by eutrophication index which is Carlson's TSI, revised carlson TSI and Walker's index, in the case of chlorophyll a, TSI values of Okgu, Oknua and Daewi reservoir is eutrophic state more than 50 and Mije and Geumgul reservoir was mesotrophic state as range of $40{\sim}50$ in TSI value. But, in the case of TP as nutrients, all reservoirs showed highly eutrophic state which was exceed to 70 in TSI value. According to above results, the water quality for small scale reservoirs in Kunsan is progressing by trophic state. therefore, for continuous use as agriculture water, we had better do establishment of management plan about water quality.

• 한국환경과학회지
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• 제13권4호
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• pp.389-401
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• 2004

Seasonal and vertical distribution of water quality were investigated from May 2001 to June 2002 in Kumoh reservoir located nearby Kumi City, Kyungpook. Kumoh reservoir that lost the role of agricultural irrigation is currently of rapid eutrophication. The vertical distribution of DO was observed clinograde with hypolimnetic anoxic zone. T-P concentrations at the surface ranged from 0.008 to 0.152 mgP/L and T-N concentrations ranged from 1.4 to 3.0 mgN/L. The vertical and seasonal variation of T-N was smaller than T-P. DOC concentrations, indicator of organic matter pollution, ranged from 2.8 to 5.4 mgC/L. Apportionment of Total-DOC (T-DOC) indicated that 14% of T-DOC was attributed to Labile-DOC(L-DOC) and the rest was due to Refractory-DOC(R-DOC). The values of TSI(Trophic State Index) ranged between 44 and 52 indicating that Kumoh reservoir is under mesotrophic condition. The results of this study indicate that Kumoh reservoir is likely to be under influence of eutrophication and thus water quality will be aggravated. Therefore, the Kumoh reservoir requires further treatment to improve water quality and a plan of the reusing water resource should be developed.

• 한국물환경학회지
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• 제24권6호
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• pp.741-749
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• 2008

Many small-scale ponds that serve as ecological habitat, recreation and irrigation are faced to eutrophication problem, which causes aesthetic nuisance and ultimately loss of their functions. Thus accurate evaluation of the trophic state of these ponds is essential to provide rational information to the stakeholders so that they can develop effective management actions. In this study, the trophic state of a small pond (Wonheung) that experiencing water quality degradation due to vicinity land development was assessed using various Trophic State Indexes (TSIs) and statistical analysis including Principal Components Analysis (PCA) based on the field monitoring data obtained from May to December, 2007. The results showed that the pond is under eutrophic state with average total nitrogen (T-N) and total phosphorus (T-P) concentrations of $708.1{\mu}g/L$ and $59.3{\mu}g/L$, respectively. The factor loading plot obtained from PCA showed distinct two influencing factors, PC 1 and PC 2. PC 1 was grouped by T-P, Chlorophyll a (Chl-a), suspended solids (SS), TN/TP ratio, and transparency that all strongly related to the eutrophication state, while PC 2 by temperature, conductivity, dissolved oxygen (DO) and turbidity that explains the seasonal water quality variations. The limiting factor was identified as light rather than phosphorus by both T-N/T-P ratio and TSI indexes analysis. The results and methodology adopted in this study can be used for water quality assessment for other small ponds and lakes.

• 한국물환경학회지
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• 제25권6호
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• pp.984-993
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• 2009

There have been growing concerns of algal growth at Daecheong reservoir due to eutrophication with excess nutrient inflow. Rainfall-driven runoff and pollutant from watershed are responsible for eutrophication of the Daecheong reservoir. In this study, two subwatersheds of the Daecheong reservoir were selected and water quality characteristics were analyzed. The L-THIA ArcView GIS model was used for evaluation of direct runoff and water quality. The $R^2$ and the EI value for direct runoff were 0.95 and 0.93 at Wol-oe watershed and were 0.81, 0.71 at An-nae watershed, respectively. The $R^2$ for SS, T-P were 0.53, 0.95 at Wol-oe watershed and 0.89, 0.89 at An-nae watershed, respectively. It has been proven that the L-THIA ArcView GIS model could be used for evaluating direct runoff and pollutant load from the watershed with reasonable accuracies.

• 한국환경과학회지
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• 제12권7호
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• pp.689-695
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• 2003

The purpose of this study is to evaluate and to predict of eutrophication in lakes by using Vollenweider-OECD model and total phosphorus concentration and inflow rate which were measured in 1993∼2001. The results of study were as follows. The annual total phosphorus loading from the watershed was calculated to be 55∼195tP/yr at lake Soyang, 221∼466tP/yr at lake Taechong, 123∼278tP/yr at lake Andong, 57∼109tP/yr at lake Seomjin. These are discharged, far the most parts, from population and fishfarm facility. TP loading on the surface area at lake Soyang was 3.01gP/㎡/yr, 2.82gP/㎡/yr, 2.84gP/㎡/yr, 3.03gP/㎡/yr, 2.34gP/㎡/yr, 1.78gP/㎡/yr, 0.91gP/㎡/yr, 0.89gP/㎡/yr, 0.86gP/㎡/yr, lake Taechong was 6.71gP/㎡/yr, 7.25gP/㎡/yr, 7.24gP/㎡/yr, 6.53gP/㎡/yr, 6.50gP/㎡/yr, 7.06gP/㎡/yr, 7.04gP/㎡/yr, 4.05gP/㎡/yr, 3.44gP/㎡/yr and TP loading on the surface area of lake Andong, lake Soemjin were 5.39gP/㎡/yr, 4.47gP/㎡/yr, 4.56gP/㎡/yr, 4.45gP/㎡/yr, 3.33gP/㎡/yr, 2.38gP/㎡/yr, 2.53gP/㎡/yr, 2.46gP/㎡/yr, 2.54gP/㎡/yr, 4.09gP/㎡/yr, 4.10gP/㎡/yr, 3.98gP/㎡/yr, 3.73gP/㎡/yr, 2.80gP/㎡/yr, 3.46gP/㎡/yr, 3.22gP/㎡/yr, 2.19gP/㎡/yr, 2.13gP/㎡/yr respectively. The tropic states of four lakes can be assessed as eutrophy because phosphorus leading exceeds the critical phosphorus loading by Vollenweider-OECD model.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2003년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.142-143
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• 2003

Seaweeds are reconsidered as the biofilter and production component in the sustainable seaweed integrated aquaculture system (SSIAS) to .educe the environmental impact of nutrient rich effluent in the coastal ecosystem. The development of the SSIAS is initiated between China and Korea to remedy the coastal eutrophication caused by fed aquacultures. (omitted)

• Environmental Engineering Research
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• 제21권3호
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• pp.284-290
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• 2016

Life cycle assessment (LCA) methodology can be used to assess impacts on the environment that might be generated during treatment of wastewater and sludge treatment. In this work, LCA methodology was suggested to evaluate monthly environmental impact of wastewater treatment plants (WWTPs). Two field scale WWTPs, A2/O process and conventional activated sludge process (CAS), were selected as target plants and the operational data were collected from those plants. As the function units, the unit volume of treated wastewater of $1m^3$ and 1 kg T-N eq. removed were selected. The environmental effect of target WWTPs operation were assessed as impact categories such as global warming potential, eutrophication potential, and so on. From monthly profiles of each index, it was shown that the environmental impact of WWTPs has seasonal patterns influenced by the influent flow rate variation causing higher impacts in winter than summer. This is due to the fact that there were no significant increase in the electricity consumption and chemical usage during the summer while the treated volume of wastewater was increased.

• 한국환경과학회지
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• 제23권6호
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• pp.1067-1074
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• 2014

Life Cycle Assessment(LCA) has been carried out to evaluate the environmental impacts of glass bottle recycle. The LCA consists of four stages such as Goal and Scope Definition, Life Cycle Inventory(LCI) Analysis, Life Cycle Impact Assessment(LCIA), and Interpretation. The LCI analysis showed that the major input materials were water, materials, sand, and crude oil, whereas the major output ones were wastewater, $CO_2$, and non-hazardous wastes. The LCIA was conducted for the six impact categories including 'Abiotic Resource Depletion', 'Acidification', 'Eutrophication', 'Global Warming', 'Ozone Depletion', and 'Photochemical Oxidant Creation'. As for Abiotic Resource Depletion, Acidification, and Photochemical Oxidant Creation, Bunker fuel oil C and LNG were major effects. As for Eutrophication, electricity and Bunker fuel oil C were major effects. As for Global Warming, electricity and LNG were major effects. As for Ozone Depletion, plate glasses were major effects. Among the six categories, the biggest impact potential was found to be Global Warming as 97% of total, but the rest could be negligible.