The objectives of this study were to analyze reservoir trophic state, based on Trophic State Index (TSI), spatial variation patterns of three zones (riverine, transition, and lacustrine zone), and empirical models through 20-years long-term data analysis. Trophic variables of TP and CHL-a were highest during the summer monsoon, and decreased along the main axis from the riverine to lacustrine zone. In the mean time, TN did not show the trend. Ratios of N:P and Secchi disc transparency (SD) increased from the riverine to lacustrine zone. The analysis of trophic state index (TSI) showed that mean TSI (TP) and TSI (CHL-a) were 62 and 57, respectively, and these values were highest in the transition zone during the summer. This zone should be managed well due to highest lake water pollution. The analysis of Trophic State Index Deviation (TSID) showed that algal growth was primarily limited by light penetration, and this was most pronounced in the monsoon season. The analysis of empirical models showed that the value of R2, based on CHL-SD model, was 0.30 (p < 0.0001) in the transition zone and the R2, based on TP-SD model, was 0.41 (p < 0.0001) in the transition zone.

Abstract
 1. 서 론
 2. 재료 및 방법
  2.1. 조사 지점
  2.2. 수질 자료 분석
  2.3. 부영화도 지수 (TSI)에 의거한 영양상태 분석
  2.4. 부영양화 주요변수의 경험적 모델
 3. 결과 및 고찰
  3.1. 대청호 수계의 강우 및 이화학적 수질 특성
  3.2. 부영양화 지수 (TSI)에 의거한 영양상태 분석
  3.3. 인공호의 경험적 모델 (Empirical Model) 분석
 4. 결 론
 감사의 글
 참고문헌

• 권혁현(충남대학교 생명시스템과학대학 생명과학과) | Hyuk-Hyun Kwon (Department of Biological Sciences, College of Biosciences and Biotechnology, Chungnam National University)
• 안광국(충남대학교 생명시스템과학대학 생명과학과) | Kwang-Guk An (Department of Biological Sciences, College of Biosciences and Biotechnology, Chungnam National University) Corresponding author