River estuaries are dynamic and productive ecosystems with high regional biodiversity. Environmental DNA (eDNA) has become a useful approach to assessing biodiversity in aquatic ecosystems. This study was conducted to investigate fish community characteristics and species diversity in two river estuary ecosystems, the Taehwa River and Changwon Stream. We further compared conventional and eDNA metabarcoding analyses of the fish communities. The conventional survey was performed in May, July, and October 2022, while the eDNA analysis was conducted only in May. We observed various fish species with different life histories, including carp, goby, and marine fish. We also found that migratory fish, such as dace Tribolodon hakonensis, sweetfish Plecoglossus altivelis, and eel Auguilla japonica, occurred in the Taehwa River, suggesting high river connectivity. Marine fish species were predominant in the Changwon Stream, as this river is located close to the sea. The diversity indices showed that the Taehwa River generally had higher species richness, evenness, and diversity values than the Changwon Stream. A total of 9-19 species were detected in the conventional survey for the three sites, whereas 11-18 species were found from eDNA analysis. The findings indicate that the sensitivity of eDNA was similar to or higher than that of the conventional method. Our study findings suggest the efficiency and efficacy of eDNA-based fish community monitoring, although with some shortcomings in applying the genetic marker to Korean fish, including no clear-cut distinction for Korean endemic species and/or genetically closely related species groups.

1. 서 론
2. 재료 및 방법
    2.1. 연구대상 지역
    2.2. 조사 방법
3. 결 과
    3.1. 이·화학적 환경 특성
    3.2. 어구를 이용한 어류 군집 구조 및 종 다양성
    3.3. 환경 DNA 어류종 탐지 및 종 다양성
    3.4. 어구를 이용한 어류 군집 현장조사와환경 DNA 분석 결과 비교
4. 고 찰
    4.1. 내륙습지 (태화강, 창원천) 하구 생태계의환경적 특성, 어류 군집 구조 및 종 다양성
    4.2. 어구를 이용한 현장조사와 환경 DNA 분석결과 비교
적 요
CRediT authorship contribution statement
Declaration of Competing Interest
사 사
REFERENCES

• 최희규(상지대학교 생명과학과 분자생태및진화학실험실) | Hee-kyu Choi (Molecular Ecology and Evolution Laboratory, Department of Biological Science, Sangji University, Wonju 26339, Republic of Korea)
• 김유림(상지대학교 생명과학과 분자생태및진화학실험실) | Yu Rim Kim (Molecular Ecology and Evolution Laboratory, Department of Biological Science, Sangji University, Wonju 26339, Republic of Korea)
• 황순영(상지대학교 생명과학과 분자생태및진화학실험실) | Soon Young Hwang (Molecular Ecology and Evolution Laboratory, Department of Biological Science, Sangji University, Wonju 26339, Republic of Korea)
• 추연수(국립생태원 습지연구팀, 인하대학교 바이오시스템융합학과) | Yeounsu Chu (Wetlands Research Team, National Institute of Ecology, Changnyeong 50303, Republic of Korea, Department of Biological Science and Bioengineering, Inha University, Incheon 22212, Republic of Korea)
• 김평범(국립생태원 습지연구팀) | Pyoungbeom Kim (Wetlands Research Team, National Institute of Ecology, Changnyeong 50303, Republic of Korea)
• 이혁제(상지대학교 생명과학과 분자생태및진화학실험실) | Hyuk Je Lee (Molecular Ecology and Evolution Laboratory, Department of Biological Science, Sangji University, Wonju 26339, Republic of Korea) Corresponding author