• 한국물환경학회지
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• 제35권4호
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• pp.352-361
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• 2019

The purpose of this study is to analyze the characteristics and correlations of the Yeongcheon Lake in order to reduce the occurrence of harmful cyanobacteria. In this study, we investigated the water quality and phytoplankton of the lake from May to November in 2017. Correlation and data mining analyses were performed to analyze the relationship between the two factors. The water temperature was lowest at the point where the Yeongcheon Lake inflow occurs at Imha Lake. It was highest at the point where the outflow occurs to Angye Lake. The pH was also highest at the outflow point, but in the case of DO, it was highest at the midpoint between the inflow and outflow. The main cyanobacteria that emerged during the study period were Oscillatorialimosa, Microcysti saeruginosa and Aphanizomenon flos-aquae. As a result of correlation analysis, the water temperature, inflow, COD loading, TOC loading at the inflow point of the Yeongcheon Lake were the items that were related to the harmful cyanobacteria. The data mining analysis indicated that the TP loading and harmful cyanobacteria in the inflow point of the Yeongcheon Lake were influential on the detrimental cyanobacteria in the Yeongcheon Lake outflow point. When the TP loading was less than 39.0 kg/day at the inflow site, it was expected that the amount of harmful cyanobacteria could be maintained below 10,000 cells/mL.

• 한국제4기학회지
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• 제19권1호
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• pp.41-46
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• 2005

This study discusses the soil erosion on hillslopes and sediment deposition in lakes within catchments in South Korea. In order to determine seasonal variations of sedimentation in Yeongcheon and Seondong lakes, the sediment traps were set in the deep part of both lakes and lake sediments have been sampledmonthly from July 2004 to August 2005. Some properties such as highmineral content, fine particle size and high particle density in the Yeongcheon Lake indicate intensive soil erosion, sediment transportation and deposition throughout the catchment for a long time. The high sediment yield in the Seondong Lake is related with higher weathering intensity and extreme soil erosion by running water due to higher seasonal rainfall amount. Rates of erosion and sedimentation in the Seondong Lake are estimated to be higher than those of the Yeongcheon Lake, suggesting that the Seondong Lake is associated with higher precipitation, smaller catchment area, and extreme soil vulnerability to ephemeral erosion by overland flow during the heavy rainfall event. Consequently, both catchments are characterized by different erosion and sedimentation processes, as well as different geomorphic factors (bedrock, soil structure, rainfall intensity and catchment area).

• 생태와환경
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• 제42권3호
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• pp.331-339
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• 2009

영천호와 대청호 어류들의 각 조직들(근육, 간, 내장, 아가미)에 농축된 microcystin-LR의 농도 및 TDI(total daily intake)값에 기초하여 인체의 건강위해성을 평가하였다 영천호의 분석결과에서 조식성(藻飾性)인 떡붕어(Carassius cuvieri)는 다른 종들과 비교하여 간을 포함한 대부분의 조직에서 높은 microcystin-LR의 농축양상을 보였다. 대청호에서 잡식성(雜食性)인 누치와 조식성인 떡붕어의 각 조직에서 높은 microcystin-LR 농도가 관찰된 가운데 내장에서는 누치와 떡붕어가 매우 높은 microcystin-LR 농도를 보였으며, 떡붕어는 다른 종들과 비교하여 내장이외에도 간과 아가미에서 높은 microcystin-LR농도를 나타내었다. 인체의 건강위해성 평가를 위해 각 조직에서 도출된 microcystin-LR의 EDI(estimated daily intake) 값들을 TDI 값과 비교하였다. 결과에서, 두 조사지역에서 모두 떡붕어(Carassius cuvieri)는 근육을 제외한 대부분의 조직들에서 EDI값들이 TDI 값을 초과하는 양상을 보였다.