Role of Macrophages in the Variability of Zooplankton Community Structure in the Litoral Zone of Shallow Lakes
V. P. SEMENCHENKO
Abstract
Distribution, daily variability and zooplankton aggregation in the litoral zone of lakes, and the influence of various macrophyte species on its community structure were considered. It is demonstrated that both direct and reverse horizontal migrations of zooplankton are caused mainly by the pressure of fishes. The influence of predatory zooplankton is of smaller importance and is directed mainly onto small-size species. The expression of horizontal migrations of zooplankton decreases with the depth, and the effect of "shore avoidance" is observed in large-sized zooplankton species and is caused not only by fishes pressure, but also by other, most probably abiotic, factors. The problem of interaction between macrophytes and zooplankton cannot be reduced only to the role of macrophytes as a refuge. Unclear remain the allelopathic properties of macrophytes, the competitive relations between separate zooplankton species in macrophyte thickets, and the influence of predatory invertebrates associated with macrophytes. Obscure is also the role of macrophytes as a factor changing hydrodynamic processes in the littoral zone of lakes.
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