The role of sediment on the energy availability for fishes in the upper Parana river floodplain/O papel do sedimento na disponibilidade de energia para peixes da planicie de inundacao do alto rio Parana

• Published in: Acta Scientiarum. Biological Sciences (UEM) 2012, Vol.34 (4), p.391
• Main Authors: Gimenes, Michele de Faveri, Takeda, Alice Michiyo, Benedito, Evanilde
• Format: Report
• Language: Spanish
• ISSN: 1679-9283
• DOI: 10.4025/actascibiolsci.v34i4.9335

This study aimed to identify potential sources of organic matter in sediment, using stable isotopes of carbon ([δ.sup.13]C) and nitrogen ([δ.sup.15]N). Sediment samples were gathered from the margin and in center of three subsystems: Ivinheima, Parana and Baia, in August/2001. The samples were fractionated granulometrically and separated by size (< 200 µm; 70-200 µm; > 70 µm), prepared and sent to CENA / USP, for identifying the isotopes proportions. Significant differences were detected in the isotopic ratios of the sediment only between sampling stations. The Baia channel presented the lowest [δ.sup.13]C values, while the highest ones were recorded in Parana river. At this last, [δ.sup.15]N values were negative (-14.41‰). We did not verify significant difference in isotopic composition between the particle sizes of sediment, and between the sampling points. The main sources of carbon for the sediment were C3 macrophytes, periphyton and particulate organic carbon (POC).