Compound specific isotope analysis of amino acids (CSIA-AAs) is being highlighted as an alternative approach for overcoming some restrictions in application of stable isotope analysis of bulk tissue (SIA) for trophic position (TP) estimation. However, this approach has rarely been applied in Korea. The present study determines TP of two Polychaeta (Nephtyidae and Glyceridae) and two fish species (Platycephalus indicus and Lophius litulon) collected from the Geum River estuary using nitrogen isotope ratio of amino acid and compared with the TP values estimated by SIA. The Polychaeta species, sampled in two sites, showed similar TP between SIA (2.7 and 3.1) and CSIA-AAs (2.6 and 3.1). However, for both fish species, TP values displayed a large difference between SIA (3.1 and 2.3) and CSIA-AAs (3.8 and 3.7). In this study TP values estimated by CSIA-AAs showed more similar to the previously reported gut content analysis of both fishes compared with the results of SIA. Current study suggests the applicability of nitrogen isotope ratio of amino acid to understand coastal ecosystem structure and trophic ecology.

서 론
 재료 및 방 법
  1. 시료 채집 및 보관
  2. Bulk tissue의 질소 안정동위원소비 분석
  3. 아미노산의 질소 안정동위원소비 분석
  4. 영양단계 산출
 결과 및 고 찰
  1. Bulk Tissue의 탄소 및 질소 안정동위원소비
  2. 아미노산의 질소 안정동위원소비
  3. 영양단계의 비교
  4. 먹이망 구조
 적 요
 사 사
 REFERENCES

• 최현태(한양대학교 해양융합공학과, Department of Marine Sciences and Convergent Technology, Hanyang University) | Choi, Hyuntae
• 최보형(한양대학교 해양융합공학과, Department of Marine Sciences and Convergent Technology, Hanyang University) | Bohyung Choi
• 신경훈(한양대학교 해양융합공학과, Department of Marine Sciences and Convergent Technology, Hanyang University) | Kyung-Hoon Shin Corresponding author