engleski

Rotifer community structure in two backwaters with different helophyte composition (Krapina River, Croatia)

Rotifer community structure was studied in two backwaters differing in the width of the littoral zone and helophyte composition. The initial aim of this study was to examine the qualitative, quantitative and trophic structure of rotifers between the littoral zone with helophytes and comparatively open water during the spring and summer. The second aim was to analyse the epiphytic rotifer structure collected from stems of Iris pseudacorus and stems and leaves of Mentha aquatica. In the mesotrophic/eutrophic backwater with a narrow littoral zone and uniform helophyte vegetation, rotifer density was high in both open water (3750 ind/L) and the littoral zone (2332 ind/L), in contrast to the mesotrophic backwater with a wide littoral zone and heterogeneous helophyte vegetation (open water 688 ind/L ; littoral zone 536 ind/L). Rotifers abundances were significantly higher in the epiphyton of the complex plant architecture (M. aquatica) in comparison to the uniform habitus (I. pseudacorus). Microfilter-feeders dominated in both backwaters and were positively correlated with food resources.

emergent macrophytes; rotifers; microfilter-feeders

nije evidentirano