Lubis, Novandi2013-05-302013-05-302013-05-30sumarnihttp://repository.unri.ac.id:80/handle/123456789/3515The research was conducted in December 2012. This study aims to knowing pelagik fish communities in Singkarak Lake with relation to water quality and also and the impact of activities around the lake. The method used in this research is the case study method. Data analysis using diversity index (H '), dominance index (C) and equitability index (E) and the value of fish abundance. Observations found five families are Cyprinidae, Tetraodontidae, Osphronemidae, Cichlidae and Anabantidae, nine genera are: Osteochilus sp, Hampala sp, Puntius sp, Osphronemus sp, Tetraodon sp, Cyclocheilichthys sp, Oreochromis sp, Trichogaster sp, and Mystacoleucus sp. Abundance values ranged 7 - 15 ind/m2; diversity index 0,4237 – 1,1566; dominance index 0,6862 – 0,8678; equitability index 0,2119 – 0,3482; temperatures ranging 29,07 – 29,77 ⁰ C; turbidity 2 - 4 NTU; pH 6; dissolved oxygen 2,70 – 3,20 mg / l, CO2 6,83 – 9,23 mg / l, COD 3,72 – 5,26 mg/l, BOD 0,94 – 1,65 mg / l. The influence of several activities such as farming, floating cages (KJA) and human settlements around the lake, led to the decline of water quality parameters in Singkarak Lake. Based on Government Regulation No.82 of 2001, the condition waters of Singkarak Lake is still in normal condition and still able to support living organisms (aquatic), especially the fish organism.otherCommunity of fishwater qualityactivitiesSingkarak Lakestudent Paper Post Degree