Abstract
The damming of a river causes dangerous consequences on structure of the environment downstream of the dam, modifying the sediment composition, which impose major adjustments in longitudinal distribution of benthic community. The construction of Engenheiro Sérgio Motta Dam in the Upper Paraná River has caused impacts on the aquatic communities, which are not yet fully known. This work aimed to provide more information about the effects of this impoundment on the structure of Chironomidae larvae assemblage. The analysis of data of physical and chemical variables in relation to biological data of 8 longitudinal sections in the Upper Paraná River showed that composition of Chironomidae larvae of stations near Engenheiro Sérgio Motta Dam differed of the other stations (farther of the Dam). The predominance of coarse sediments at stations upstream and finer sediments further downstream affected the choice of habitat by different morphotypes of Chironomidae and it caused a change in the structure of this assemblage in the longitudinal stretch.
Highlights
Hydro-morphological features of rivers reflect longterm climatic and geomorphological processes which are influenced by global changes (Syrovátka et al, 2009) and, by anthropogenic impacts such as mining, dam construction, artificial eutrophication, river canalization and recreation (Dudgeon, 1994)
The knowledge of distribution patterns of river biota and habitat preferences is fundamental to effective assessment of possible effects of anthropogenic impacts on fluvial ecosystems
The objective of the work was to answer to two questions: 1) how Engenheiro Sérgio Motta Dam influences on Chironomidae larvae along the main channel of Upper Paraná River and 2) how structure of larvae assemblage changes in a stretch of 85 km
Summary
Hydro-morphological features of rivers reflect longterm climatic and geomorphological processes which are influenced by global changes (Syrovátka et al, 2009) and, by anthropogenic impacts such as mining, dam construction, artificial eutrophication, river canalization and recreation (Dudgeon, 1994). More information on the effects of impoundment to identify adverse impacts on the aquatic environment becomes necessary due to the increase of regulation of rivers flows worldwide (Petts, 1989; Dynesius and Nilsson, 1994). The knowledge of distribution patterns of river biota and habitat preferences is fundamental to effective assessment of possible effects of anthropogenic impacts on fluvial ecosystems.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
