As a result of analysis based on the observed data for BOD, COD and TOC in order to manage non-biodegradable organics in the Geumho River, COD/BOD ratio was analyzed as the occupying predominance proportion. In this study, the classification(changes in water quality measurement : increase, equal, decrease) and measurement of BOD and COD were analyzed for trends over the past 10 years from 2005 to 2014 in the Geumho River. The Geumho River is expected to need non-biodegradable organics management because BOD was found to be reduced 61.1% and COD was found to be increased 50%. As a result of the analysis of land use, the Geumho-A is a unit watershed area of 921.13 km2, which is the most common area that is occupied by forests. The Geumho-B is a unit watershed area of 436.8 km2, which is the area that is highest occupied by agriculture and grass of 24.84%. The Geumho-C is a unit watershed area of 704.56 km2 accounted for 40.29% of the entire watershed, which is the area that is occupied by urban of 15.12%. Load of non-biodegradable organics, which is not easy biodegradable according to the discharge, appeared to be increased because flow coefficient of COD and TOC at the Geumho-B were estimated larger than 1 value. The management of non-point sources of agricultural land is required because the Geumho-B watershed area occupied by the high proportion of agriculture and field. In this segment it showed to increase the organics that biodegradation is difficult because the ratio of BOD and TOC was decreased rapidly from GR7 to GR8. Thus, countermeasures will be required for this.

Abstract
 1. 서 론
 2. 재료 및 방법
  2.1. 대상유역 및 자료분석
  2.2. 유기물분석방법
  2.3. 상관분석(Correlation analysis)
  2.4. 회귀분석(Regression analysis)
  2.5. LOWESS(Locally Weighted Scatter plot Smoother)경향분석
 3. 결과 및 토의
  3.1. 금호강 본류 수질 현황
  3.2. 금호강 본류의 유기물질 오염도 현황
  3.3. TOC와 BOD, COD 유기물의 상관분석 및 회귀분석
  3.4. 금호강 본류의 유기물 농도 분포
  3.5. GIS를 이용한 토지 이용 분석
  3.6. 경험식을 이용한 오염물질 유출특성 분석
  3.7. BOD/TOC ratio를 이용한 고찰
 4. 결 론
 REFERENCE

• 정강영(국립환경과학원 낙동강물환경연구소) | Kang-Young Jung (Nakdong River Environment Research Center, National Institute of Environmental Research)
• 안정민(국립환경과학원 낙동강물환경연구소) | Jung-Min Ahn (Nakdong River Environment Research Center, National Institute of Environmental Research)
• 이경락(국립환경과학원 낙동강물환경연구소) | Kyung-Lak Lee (Nakdong River Environment Research Center, National Institute of Environmental Research)
• 이인정(국립환경과학원 낙동강물환경연구소) | In-Jung Lee (Nakdong River Environment Research Center, National Institute of Environmental Research)
• 유재정(국립환경과학원 낙동강물환경연구소) | Jae-Jeong Yu (Nakdong River Environment Research Center, National Institute of Environmental Research)
• 천세억(국립환경과학원 낙동강물환경연구소) | Se-Uk Cheon (Nakdong River Environment Research Center, National Institute of Environmental Research)
• 김교식(경북대학교 토목공학과) | Kyo-Sik Kim (Department of Civil Engineering Kyungpook National University)
• 한건연(경북대학교 토목공학과) | Kun-Yeun Han (Department of Civil Engineering Kyungpook National University) Corresponding author