Monthly Variation Analysis of BOD, COD and TOC using Long-term Observation Data in the Downstream of the Nam River

남강 하류부에서 장기관측 자료를 이용한 유기물과 생물학적/화학적 산소요구량의 월 변동 분석

  • Kang, Dong-hwan (Environmental Research Institute, Pukyong National University) ;
  • So, Yoon Hwan (Environmental Research Institute, Pukyong National University) ;
  • Park, Kyeong-Doek (Interdisciplinary Program of Marine Convergence Design, Pukyong National University) ;
  • Kim, Il-kyu (Department of Environmental Engineering, Pukyong National University) ;
  • Kim, Byung-Woo (K-water Research Institute, Korea Water Resources Corporation)
  • 강동환 (부경대학교 환경연구소) ;
  • 소윤환 (부경대학교 환경연구소) ;
  • 박경덕 (부경대학교 마린융합디자인협동과정) ;
  • 김일규 (부경대학교 환경공학과) ;
  • 김병우 (한국수자원공사 K-water연구원)
  • Received : 2018.12.24
  • Accepted : 2019.05.15
  • Published : 2019.06.30


In this study, monthly average values of BOD, COD, and TOC observed for 10 years (2008-2017) in the Nam River were estimated, and monthly variations of BOD, COD, and TOC were analyzed. Monthly average COD was always higher than monthly average BOD; monthly average TOC was high from June to September when rainfall was high. Monthly correlation coefficients between BOD and COD ranged from 0.57 to 0.94, those between BOD and TOC from 0.45 to 0.93, and those between COD and TOC from 0.75 to 0.93. The correlation coefficients were high from November to February when rainfall was low. Regression analyses for monthly average water quality data of the Nam River classified into dry season (October to April) and wet season (May to September) were conducted. Correlation coefficients were higher in the dry season than those in the wet season, and the determination coefficients of linear regression functions for BOD and COD with TOC were also higher in the dry season than those in the wet season. From this study, it can be concluded that it is appropriate to use monthly data to analyze the correlations among BOD, COD, and TOC in the stream. To analyze the relationship between TOC flowing into the stream and BOD/COD, it was found that seasonal characteristics should be considered.


Supported by : 국토교통과학기술진흥원


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