Influence of peak flow changes on the macroinvertebrate drift downstream of a Brazilian hydroelectric dam/Influencia de alteracoes de vazao sobre a deriva de macroinvertebrados a jusante de uma barragem hidreletrica brasileira

• Published in: Brazilian journal of biology 2013-11, Vol.73 (4), p.775
• Main Authors: Castro, D.M.P, Hughes, R.M, Callisto, M
• Format: Article
• Language: English
• Subjects: Dams; Hydroelectric plants; Studies; Water quality
• ISSN: 1519-6984; 1678-4375
• DOI: 10.1590/S1519-698420130004000013

Successive daily peak flows from hydropower plants can disrupt aquatic ecosystems and alter the composition and structure of macroinvertebrates downstream. The authors evaluated the influence of peak flow changes on macroinvertebrate drift downstream of a hydroelectric plant as a basis for determining ecological flows that might reduce the disturbance of aquatic biota. The aim of this study was to assess the influence of flow fluctuations on the seasonal and daily drift patterns of macroinvertebrates. The authors collected macroinvertebrates during fixed flow rates (323 ... in the wet season and 111 ... in the dry season) and when peak flows fluctuated (378 to 481 ... in the wet season, and 109 to 173 ... in the dry season) in 2010. The authors conclude that macroinvertebrate assemblages downstream of dams are influenced by daily peak flow fluctuations. When making environmental flow decisions for dams, it would be wise to consider drifting macroinvertebrates because they reflect ecological changes in downstream biological assemblages. (ProQuest: ... denotes formulae/symbols omitted.)