Hydrobiological study of the Bobrava rivulet

Abstract

The qualitative and quantitative composition of macrozoobenthos in the Bobrava rivulet was summarized utilizing former and recent studies. Altogether, 187 taxa of macrozoobenthos were determined in the Bobrava rivulet and its tributaries until now. The highest values of macrozoobenthos were found on the stony substrate with mean values of biomass and density corresponding to 18.7 g . m−2 and 2922 ind . m−2, respectively. Lower values were determined on the muddy and sandy substrates with 12.4 g . m−2 and 1587 ind . m−2, and 4.2 g . m−2 and 531 ind . m−2, respectively. The index of saprobity upstream the town Rosice corresponded to oligo-betamesosaprobity. Downstream the towns of Rosice, Omice and Radostice on the middle course of the Bobrava rivulet, water duality declined to beta – to alphamesosaprobity. Due to the self-purification ability of the stream, its water quality was improved to beta-mesosaprobity bellow the municipal pollution sources in the river stretch between localities Závist and Želešice.

Keywords

• Bobrava rivulet
• quality and quantity of zoobenthos
• index of saprobity