Annual development of the zoobenthos of the middle course of the Dyje River

Abstract

The qualitative and quantitative composition of the macrozoobenthos in the middle course of the Dyje River downstream the Znojmo reservoir was carried out in the years 2007 to 2008. Altogether, 118 taxa of macrozoobenthos were determined in the section between localities Tasovice and Dyjákovice. The highest values of macrozoobenthos were found on the stony substrate with mean values of biomass and density corresponding to 25.4 g . m−2 and 6 033 ind . m−2, respectively. Lower va­lues were determined on the sandy substrates with 5.8 g . m−2 and 5 857 ind . m−2, respectively. The index of saprobity on the locality Tasovice corresponded to betamesosaprobity (Si = 1.70), for the lo­ca­li­ty Dyjákovice the same index was (Si = 1.80).

Keywords

• Dyje River
• quality and quantity of zoobenthos
• indices of saprobity