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Impact of long-term alternations of discharge and spate on the chironomid community in the lowland Widawka River (Central Poland)

✍ Scribed by Maria Grzybkowska; Alina Temech; Małgorzata Dukowska


Publisher
Springer
Year
1996
Tongue
English
Weight
570 KB
Volume
324
Category
Article
ISSN
1573-5141

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✦ Synopsis


Spatial and temporal distribution, abundance and production of macroinvertebrate communities were estimated over two years in a fifth-order section of the Widawka River . Discharge of this river has been increased artificially by coal mine water inputs. Additionally, during the second year, one of the highest discharges of the current 20-year period was recorded . Chironomidae were co-dominant in macrobenthos, both in a straight reach (WIA) and in a meandering site (WIB) . More mosaic habitats resulted in higher densities of midges, reaching 6215 ind .m -2 in year 1 and 1141 ind .m -2 in year 2 at WIA, while at WIB 896 densities were ind .m-2 and 257 ind .m -2 , respectively . Flooding affected the distribution and abundance of the chironomid assemblages . Recolonization by psammophilous Polypedilum began after the various microhabitats were buried with sand . Chironomid production was estimated on a species-specific basis for the dominant taxa . In year 1 (mean annual water temperature 10 .0° C) chironomid production was 12 .4 g dry wt m -2 yr1 at WIA and 1 .9 g dry wt m -2 yr -1 at WIB . These values sharply decreased in year 2 (mean annual water temperature 9 .8° C) reaching 1 .9 g dry wt m -2 yr 1 at WIA and 0.4 g dry wt m-2 yr -1 at WIB, as effects of the high spate .