Zooplankton in a Danube River Arm near Rusovce (Slovakia)

Abstract

. Small species, Bosmina longirostris and Chydorus sphaericus were dominant. Only four adult Copepoda -Cyclops vicinus, Thermocyclops crassus, Eurytemora velox and Eudiaptomus gracilis -were recorded in quantitative samples of both years. In the zooplankton assemblage dominated rotifers (Synchaeta pectinata, Synchaeta oblonga, Polyarthra dolichoptera and Keratella cochlearis) which represented 78% and 67% of total abundance respectively. The total of 19 species of rotifers, 34 Cladocera species and 16 taxa of Copepoda were found.

Similarities in zooplankton community between River Drawa and its two tributaries (Polish part of River Odra)

“…Moreover, our results indicate that the zooplankton of the two small Drawa tributaries could be influenced by the chemical conditions of the lakes from which they flowed, but the structure of the zooplankton in the River Drawa was most probably shaped by the hydrological and biological conditions of the River Drawa and its tributaries. The increase of zooplankton abundance in the Drawa River from S1 to S5 can be surprising as it is generally assumed that the abundance, biomass and body length of zooplankton decrease with distance from the lake (Armitage & Capper, 1976;Sandlund, 1982;Walks & Cyr, 2004;Illyová, 2006;Chang et al, 2008;Illyová et al, 2008). However, in the environmental conditions of the area studied a potential positive effect of the tributaries on the Drawa zooplankton was expected.…”

“…The influence of the Stary Potok with its fast current and regular bed was greater but manifested only in the contribution of small Rotifera, small Cladocera or juvenile stages of Copepoda, especially Keratella sp., Bosmina sp. and Nauplius Cyclopoida, which are often seen in river plankton (Szlauer, 1977;Czerniawski, 2008;Illyová et al, 2008). It can be probably related to the nutritional selectivity of fish, that is the lack of their interest in small species (Chang et al, 2008).…”

Zooplankton communities of two lake outlets in relation to abiotic factors

“…Little is known about zooplankton communities found in flowing water bodies. The majority of authors concerned with this subject studied large or relatively large rivers [4][5][6][7] in which the density of zooplankton is greater than in small rivers. In lake outlets, the number of zooplankton species, their density and their body length decreases with increasing distance downstream along rivers [8,9].…”

Potamozooplankton communities in three different outlets from mesotrophic lakes located in lake-river system

“…Davidson et al 2000, Thorp & Mantovani 2005, Illyová et al 2008). However, it should be noted that the zooplankton community of large rivers is much better known than the zooplankton community of small rivers or small streams.…”