Original paper

The influence of different hydrological conditions on periphytic invertebrate communities in a Danubian floodplain

Vidaković, Jasna; Čakalić, Ivana Turković; Stević, Filip; Čerba, Dubravka


Changes in the hydrologic regime have been a driving force for maintaining biodiversity of floodplain communities. Recent studies have shown that periphytic biomass is closely related to the hydrologic cycle and disturbances caused by flood pulses. This study was conducted in Lake Sakadaš which is a part of one of the largest conserved Danube floodplains, Kopački Rit in Croatia. The aim of our study was to determine colonization patterns, invertebrate abundance and community structure within the periphyton community that developed on artificial substrates during two hydrologically different years. Low connectivity of the floodplain was present in 2008 while high connectivity of the floodplain and extreme flooding characterized 2009. There were two distinct phases in the invertebrate colonization process. The early phase of colonization, which included the first four sampling dates of both years, was characterized by Crustacea. The late phase of colonization differed between the research years. Bivalvia (Dreissena polymorpha) was the most dominant taxonomic group in the late phase of colonization in 2008, while Oligochaeta was the representative taxa in late phase of 2009. In 2008, food source and water temperature were the most important factors influencing the late periphytic invertebrate community, while the most important parameters influencing fauna in 2009 was the Danube water level, indicating the influence of the flood pulse on the invertebrate community. Generally, the invertebrate community differed between the two years in both composition and abundance. One of the most important differences was a substantial development and the dominance of an invasive bivalve species, Dreissena polymorpha indicating a possible threat to the lake's ecosystem suggesting the need for further monitoring.


flood pulsefloodplain connectivityperiphytoninvertebrate communitydreissena polymorpha