Abstract: | A fish‐based Index of Biotic Integrity (IBI) was adapted for use in a stream of the heavily impacted Piracicaba River basin in southeastern Brazil. The influences of land use (mainly sugar‐cane crops) and an urban area on the fish community were investigated at ten sites along a 17 km‐long stream during the dry and rainy season. The IBI varied with the season and location along the stream, reflecting differences between the agricultural and urban sites, which were more pronounced during the dry season. The final index was positively correlated with a Habitat Quality Index (dry season) but not with a Water Quality Index. The results can be viewed as a tool for assessing and monitoring the ecological health of streams in this watershed. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) |