L. Forró szerk.: Miscellanea Zoologica Hungarica 10. 1995 (Budapest, 1995)
Gulyás, P., Bancsi, I.; Zsuga, V.: Rotatoria and Crustacea fauna of the Hungarian watercourses
2. Túr 57 Rotatoria and 2 Cladocera taxa were found, the dominance of planktonic eutrophic elements were characteristic (Brachionus, Cephalodella, Synchaeta, Trichocerca genera). As a result of high water velocities species number and biomass was low, the latter changed between 0.01 - 0.24 g/m 3 . 3. Szamos 59 Rotatoria taxa occurred here, the microcrustacean fauna was rather poor. On the Tisza watershed this is one of the most polluted streams. Large quantities of organic and inorganic pollutants are carried by this river into the Tisza causing extreme water quality conditions (alpha-mesosaprobic state), especially with regards to dissolved oxygen content. These conditions might have been caused by the low water and warm weather as well. Zooplankton biomass values in the Szamos in 1992 were 0.01 - 67.36 g/m , which is extremely high considering the whole watershed, and are characteristic to eupolytrophic, polytrophic stagnant waters. Large biomass is due to Anuraeopsis fissa, Filinia longiseta, Trichocerca pusilla, Polyarthra vulgaris, and Brachionus and Keratella species. 4. Kraszna Belongs to polluted watercourses. From the 59 taxa of Rotatoria fauna dominance of cosmopolitan, euryeocious species was observed, with high abundance of pollution indicator Rotatoria species. Only few crustaceans were found. Zooplankton communities can be characterized by the occurrence of Bdelloidea, Brachionus, Cephalodella, Euchlanis, Lecane species. Biomass values were between 0.08 - 1.03 g/m 3 . 5. Lónyai csatorna Occurrence of 48 Rotatoria and 2 Cladocera taxa was recorded. Among these species planktonic, metaphyton and benthic organisms were also found, but cosmopolitan, well adaptable species dominated the community. Biomass values varied between 0.01 - 1.01 g/m 3 , most probably due to the polluted character of the channel (frequently alpha-mesosaprobic, poly-alpha-mesosaprobic) and the presence of toxic materials. Also belonging to the more polluted stream categoiy, among the Rotatoria organisms organic detritus feeders were represented in high proportion. 6. Bodrog 39 Rotatoria, 5 Cladocera and 1 Copepoda taxa were recorded, the fauna was dominated by planktonic organisms, the stream belongs to the cleaner, less polluted category. Seasonal changes are characteristic to the Zooplankton community, in summer Keratella cochlearis, K. cochlearis tecta, Filinia longiseta, Anuraeopsis fissa, Brachionus calyciflorus and B. quadridentatus had large abundances. Zooplankton biomass changed between about 0.01 - 3.44 g/m .
