L. Forró szerk.: Miscellanea Zoologica Hungarica 10. 1995 (Budapest, 1995)

Tittizer, T., Leuchs, H.; Banning, M.: The consequences of river impoundments for the macrozoobenthos - demonstrated at the example of the River Danube in Germany

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] Danube-km weir Fig. 8. Average population densities of chironomid larvae in the longitudinal profde of the Geisling impoundment (examination in April, July and September 1989) [Ind./m'l 0,6-lOOmml «on« [>10Omn,l Fig. 9. Average population densities of chironomid larvae (subfamily Chironominae) in dependence on substrate (examination 1989; rkm 2354-2376) avoid both the areas of extremely low velocities of flow with silt deposits and the zones where flow velocities are higher, in the range typical for running waters. The maximum of larvae was found in areas of middle velocities of flow between 0.2 and 0.3 m/s (Fig. 10). Fig. 11 shows certain preference for water depths between 2 and 5 m. As it was mentioned before, in the Havel river lakes Glyptotendipes larvae also preferred such areas, as Wundsch (in