Zooplankton communities of two lake outlets in relation to abiotic factors

Abstract

We examined the quantitative and qualitative zooplankton community structure in two small rivers flowing out from lakes differing in trophic conditions. Within each river, three sites were chosen for the collection of drifted zooplankton: one at the outflow, and two at distances of 0. 2 km and 1 km from the outflow. The most significant difference in zooplankton community between the outflow and the lower course of the river occurred in the first section directly after the outflow. These differences in the zooplankton community were driven largely by crustaceans, which declined faster in the river flowing out from the mesotrophic lake. Physical parameters mainly impacted the zooplankton community found in the river flowing from the mesotrophic lake; however, chemical parameters also had an impact in the river discharging from the strongly eutrophic lake. © 2010 Versita Warsaw and Springer-Verlag Berlin Heidelberg.