This study identified the effect of changes in the riverbed on the benthic macroinvertebrate communities. The benthic macroinvertebrates collected from the surveyed sites belonged to 119 species, 65 families, 20 orders, and 7 classes in 4 phyla. The number of Ephemeroptera, Plecoptera, and Trichoptera (E.P.T) species was 42, 10, and 8, respectively, in the tributary, confluence, and Nakdong River sites. Lotic species (Hydropsychidae) showed a high density at the tributary sites, whereas lentic species (Chironomidae) showed a high density at the confluence and Nakdong River sites. Community analysis showed that the Dominance Index (DI) was 0.54 in tributary sites, and dominance indices increased closer to the Nakdong River sites. The diversity index (H’) was inversely proportional to DI. The ratio of Burrowers species (BU) at the surveyed sites increased closer to the Nakdong River sites. Analysis of common species showed 37 species (34.6%) between the tributary and confluence sites and 66 species (51.5%) between the confluence and Nakdong River sites.

Abstract
 1. 서 론
 2. 재료 및 방법
  2.1. 조사지점 및 조사시기
  2.2. 현장 조사 및 분석
  2.3. 자료 분석
 3. 결 과
  3.1. 종조성 및 E.P.T. 점유율
  3.2. 군집지수 분석
  3.3. 서식기능군(FHGs) 분석
  3.4. 조사지점간 공통 출현종 분석
  3.5. 군집안정성 분석
 4. 고 찰
 REFERENCES

• 이슬희(안동대학교 생명과학과) | Seul Hee Lee (Department of Biological Science, Andong National University)
• 이미진(안동대학교 생명과학과) | Mi Jin Lee (Department of Biological Science, Andong National University)
• 서을원(안동대학교 생명과학과) | Eul Won Seo (Department of Biological Science, Andong National University)
• 이종은(안동대학교 생명과학과, 안동대학교 환경연구소) | Jong Eun Lee (Department of Biological Science, Andong National University, Environment Research Center, Andong National University) Corresponding author