Total of 325 estuaries in Korea were surveyed to analyze the effect of presence of sluice gate on the estuary environment and fish community from 2016 to 2018. Fish community in closed and open estuaries showed differences generally, and the relative abundance (RA) of primary freshwater species in the closed and migratory species in the open estuaries were high. The result of classifying species by habitat characteristics in closed and open estuaries showed similar tendencies at the estuaries of south sea and west sea. The relative abundances of primary freshwater species in the closed estuaries at the estuaries of south sea and west sea were the highest, but estuarine and migratory species were high in both closed and open estuaries at the estuaries of east sea. Primary freshwater species showed higher abundances in the closed estuaries with reduced salinity due to blocking of seawater since they are not resistant to salt. However, primary freshwater species in open estuaries at east sea was higher than that of the closed estuaries, which is considered to be the result of reflecting the characteristics (tide, sand bar, etc.) of the east sea. Korea Estuary Fish Assessment Index (KEFAI) was showed to be higher at open estuaries than closed in all sea areas (T-test, P<0.001), the highest KEFAI was observed in closed estuaries at south sea, and open estuaries in east sea. Fish community of closed and open estuaries in each sea areas showed statistically significant differences (PERMANOVA, East, Pseudo-F=3.0198, P=0.002; South, Pseudo-F=22.00, P=0.001; West, Pseudo-F=14.067, P=0.001). Fish assemblage similarity by sea areas showed a significant differences on fish community in closed and open estuaries at east sea, south sea, and west sea (SIMPER, Group dissimilarity, 85.85%, 88.36%, and 88.05%). This study provided information on the characteristics and distribution of fish community according to the types of estuaries. The results of this study can be used as a reference for establishing appropriate management plans according to the sea areas and type in the management and restoration of estuaries for future.

Abstract
서 론
재료 및 방 법
    1. 조사지점 및 시기
    2. 현장 조사
    3. 하구어류평가지수 (KEFAI, Korea Estuary FishAssessment Index)
    4. 분석 방법
결 과
고 찰
적 요
REFERENCES

• 김준완(공주대학교 생물교육과) | Jun-Wan Kim (Department of Biology Education, Kongju National University)
• 김규진(공주대학교 생물교육과) | Kyu-Jin Kim (Department of Biology Education, Kongju National University)
• 최범명(공주대학교 생물교육과) | Beom-Myeong Choi (Department of Biology Education, Kongju National University)
• 윤주덕(국립생태원 멸종위기종복원센터) | Ju-Duk Yoon (Research Center for Endangered Species, National Institute of Ecology)
• 박배경(국립환경과학원 물환경공학연구과) | Bae-Kyung Park (Water Environmental Engineering Research Division, National Institute of Environmental Research)
• 김종학(국립환경과학원 물환경공학연구과) | Jong-Hak Kim (Water Environmental Engineering Research Division, National Institute of Environmental Research)
• 장민호(공주대학교 생물교육과) | Min-Ho Jang (Department of Biology Education, Kongju National University) Corresponding author