Flood-Pulse Effects on Zooplankton Assemblages in a River-Floodplain System (Gemenc Floodplain of the Danube, Hungary)

We studied the structure and population dynamics of zooplankton assemblages in the water bodies (eu-, para-, plesiopotamal and conjunctive water bodies) of a temperate floodplain during flood events. Here we report differences in the species composition of these water bodies in the two stages of flood pulses: rising vs. receding. During the receding period the proportion of larger and tychoplanktonic species increased. Similarity among zooplankton assemblages of these floodplain water bodies increased during the rising and decreased during the receding period. Species richness, diversity and population density values of zooplankton assemblages increased during the receding period in all types of water bodies except the eupotamal. The guild ratio of rotifer assemblages showed characteristic, but somewhat ambiguous changes. We conclude that the hydrological regime affects the structure and dynamics of zooplankton assemblages on the floodplain. ((c) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)