• Proceedings of the KSRS Conference
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• v.2
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• pp.909-912
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• 2006

In this paper a method for remotely-sensed assessment of eutrophication was experimented. The water samples were collected for analysis of COD (chemical oxygen demand) and nutrients concentration, and the remote sensing reflectance data at the sampling points were synchronously measured using above-water method in two cruises, which were conducted in the Pearl River Estuary in January 2003 and January 2004 respectively. Based on the in-situ data the local algorithms for estimation of concentration of nutrients (P and N) and COD were developed by Partial Least Squares (PLS) regression. The algorithms were then applied to atmospheric-corrected SeaWiFS data and the COD and nutrients concentration in Pearl River Estuary were estimated. And then the assessment of eutrophication was carried out by comparison of the estimated nutrients and COD value with the water quality standard. The results show that the whole estuary is seriously in eutrophication.

• Journal of Environmental Impact Assessment
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• v.15 no.1
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• pp.35-43
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• 2006

The eutrophication in lakes is caused by the inflow of excessive nitrogen and phosphorus, which are not only pollutants to reduce the value of water resource but also nutrients for algae growth that debases water quality. Several methods have been used to judge the eutrophication grades of lakes, but the judgment results can be different with one another even under same coditions because each method is different in judgment items and their standards. A method for overcoming the problem with the judgment of eutrophication grades is, therefore, developed in this study with the application of fuzzy theory. This method allows decision makers to represent the uncertainties (differences) of results by the existing judgment methods and also incorporate associated uncertainties directly into the judgment process, so the judgment results can be made that are more realistic and consistent than those made without taking uncertainty in account.

• Journal of Environmental Health Sciences
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• v.34 no.1
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• pp.62-69
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• 2008

The life cycle assessment method for environmental impact assessment was used, in this study, to assess the production process of wheat flour which is the most important material in the food industry. Environmental impact assessments were compared between that of the Ministry of Environment, Republic of Korea (method I) with that of the Ministry of Commerce, Industry and Energy (method II). Life cycle inventories (LCI) was performed using internal and external databases and the production statistics database of company S. The procedure of life cycle impact assessment (LCIA) was followed in terms of classification, characterization, normalization and weighting to identify the key issues. The impact categories of method I were divided into 8 categories with consideration of : abiotic resources depletion, global warming, ozone depletion, photochemical oxidant creation, acidification and eutrophication. The impact categories of method II were divided into 10 categories with consideration of: abiotic resources depletion, global warming, ozone depletion, photochemical oxidant creation, acidification, eutrophication, human toxicity, freshwater aquatic ecotoxicity, marine aquatic ecotoxicity and terrestrial ecotoxicity.

• Environmental Analysis Health and Toxicology
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• v.28
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• pp.2.1-2.7
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• 2013

Objectives Tricalcium phosphate and calcium hydrogenorthophosphate are high production volume chemicals, mainly used as foodstuff additives, pharmaceuticals, lubricants, synthetic resin, and disinfectants. Phosphate has the potential to cause increased algal growth leading to eutrophication in the aquatic environment. However, there is no adequate information available on risk assessment or acute and chronic toxicity. The aim of this research is to evaluate the toxic potential of phosphate compounds in the aquatic environment. Methods An aquatic toxicity test of phosphate was conducted, and its physico-chemical properties were obtained from a database recommended in the Organization for Economic Cooperation and Development (OECD) guidance manual. An ecotoxicity test using fish, Daphnia, and algae was conducted by the good laboratory practice facility according to the OECD TG guidelines for testing of chemicals, to secure reliable data. Results The results of the ecotoxicity tests of tricalcium phosphate and calcium hydrogenorthophosphate are as follows: In an acute toxicity test with Oryzias latipes, 96 hr 50% lethal concentration ($LC_{50}$) was >100 (measured:>2.14) mg/L and >100 (measured: >13.5) mg/L, respectively. In the Daphnia test, 48 hr 50% effective concentration ($EC_{50}$) was >100 (measured: >5.35) mg/L and >100 (measured: >2.9) mg/L, respectively. In a growth inhibition test with Pseudokirchneriella subcapitata, 72 hr $EC_{50}$ was >100 (measured: >1.56) mg/L and >100 (measured: >4.4) mg/L, respectively. Conclusions Based on the results of the ecotoxicity test of phosphate using fish, Daphnia, and algae, $L(E)C_{50}$ was above 100 mg/L (nominal), indicating no toxicity. In general, the total phosphorus concentration including phosphate in rivers and lakes reaches levels of several ppm, suggesting that phosphate has no toxic effects. However, excessive inflow of phosphate into aquatic ecosystems has the potential to cause eutrophication due to algal growth.

• Journal of Environmental Impact Assessment
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• v.23 no.3
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• pp.220-226
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• 2014

This study investigated temporal-spatial and variations in Geostationary Ocean Color Imager (GOCI) products of parameters total suspended solids (TSS) and chlorophyll-a in the North Marine Areas of East China Sea.GOCI data were collected daily from February 2012 to December 2012. The higher chlorophyll-a values were observed during the investigation period. The relatively large increase in TSS and chlorophyll-a at the sampling stations coupled with typhoon events during the summer rainy period. The abnormal chlorophyll-a concentration was mainly driven by meteorological factors such as typhoon and rainfall in the coastal areas of Jeju and the North Marine Areas of East China Sea. The abnormal high chlorophyll-a concentration at the majority of the coastal stations indicate eutrophication of coastal waters, especially Red tide. The events such as eutrophication and abnormal high chlorophyll-a concentration may potentially influence outbreak of Red Tide, detected with GOCI parameters.

• Environmental Engineering Research
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• v.21 no.3
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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.

• Journal of Environmental Science International
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• v.23 no.6
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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.

• Transactions of the Korean hydrogen and new energy society
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• v.29 no.1
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• pp.111-116
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• 2018

The environmental impacts of a 1 kW polymer electrolyte membrane fuel cell (PEMFC) system are quantitatively assessed by performing a Life Cycle Assessment (LCA) study. A PEMFC system produces electricity and heat simultaneously, so an appropriate allocation of associated inputs and outputs is performed between the electricity and heat produced. The environmental impacts of the PEMFC system on the impact categories such as global warming (GW), abiotic depletion (AD), acidification (AC), and eutrophication (EU) are assessed from the life cycle impact assessment. The impact indicator results of the impact assessment on these impact categories are obtained as $3.70E-01kg\;CO_2\;eq./kWh$, 1.86E-03 kg Sb eq./kWh, $4.09E-04kg\;SO_2\;eq./kWh$, and $1.88E-05kg\;PO_4{^{3-}}/kWh$, respectively. For all impact categories studied the most influential stage is the operation stage, which accounts for 98.8%, 98.7%, 70.3%, and 62.3% of the total impact on GW, AD, AC, and EU, respectively. For the impact categories of AD, AC, and EU, most of the environmental impacts during the operation stage is attributed to the production of city gas. However, for the impact category of GW, $CO_2$ emission from the reforming process of city gas is the main reason for the largest contribution of the operation stage to the total impact results.

• Journal of Environmental Impact Assessment
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• v.17 no.6
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• pp.349-356
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• 2008

This paper aims to understand the effects of a turbidity flow intrusion on eutrophication in Daecheong Dam Reservoir. CE-QUAL-W2, a two-dimensional hydrodynamic and water quality model, is applied. The elevation of the reservoir water surface is used to validate the hydrodynamic model parameters and maximum fluctuations in the water surface elevations reaches about 1 m in the reservoir. During the heavy storm season, July, the thermocline submerged to less than 30 m below the surface. The thickness of the thermocline also reduced to 10 to 15 m. While the average TSS in June, the beginning of the monsoon was still low but it peaked in July due to heavy rainfall. Vertical profiles of the TSS regime in July indicated higher concentration in upper water layers and then the regime moves gradually downward in accordance with the time lapse. Due to the dam spillway opening, high concentrations of TSS attributed to storm turbidity ascended to the upper water layer by following the upward current movement and then, the regime precipitated to a layer below 30 to 40 m after September.

• Korean Journal of Environmental Agriculture
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• v.24 no.4
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• pp.334-340
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• 2005

This experiment was conducted to evaluate the nutrient loss and to assess the eutrophication into small stream by intensive rains in the steeped cornfield during cultivation. The crop cultivated was a soiling com (DW5969), and the experimental plots were divided into two parts that were 10 and 18% of slope degrees. The amount of T-N and T-P loss was calculated by analysis of surface run-off water quality, and was investigated the effect of eutrophication to small stream as a part of life cycle assessment (LCA) methodology application. For the surface run-off water quality, EC and T-N values were highest in first runoff event as compared to the other events and maintained the stage state with litter variations at every hour during the runoff period except for EC in the slope 18%. However, T-P concentration has been a transient stage after runoff event of July 27. Total surface run-off ratio was not significantly different with slope degrees, but amount of T-N and T-P losses at 18% of slope were high as $5.96kg\;ha^{-1}\;and\;0.65kg\;ha^{-1}$ as relative to 10% of slope degree, respectively. Furthermore, T-N losses from run-off water in the sloped cornfield 10 and 18% were approximately 9.8 and 12.5% of the N applied as fertilizer when the fertilizer applied at recommended rates after soil test, respectively. For the eutrophication impact to the small stream, it was shown that $PO_4$ equivalence and Eco-indicator value at 18% of slope degree were greater as much $6.11kg\;ha^{-1}$ and 0.81 as compared to the slope angle 10%, respectively. Therefore, it was appeared that each effect of nutrient losses, eutrophication and Eco-indicator value was enhanced according with higher slope degree.