Water temperature of the littoral zone during the domination of the blue-green algae Planktothrix agardhii and Limnothrix redeckei in the composition of phytoplankton in the polytrophic lake Jeziorak Mały

Studies were carried out on net phytoplankton of an urban Lake Jeziorak Mały, Mazurian Lakeland. Samples collected in 1996 showed domination of blue-green algae(67% of the total phytoplankton number). Limnothrix redeckei and Plankto-thrix agardhii were particularly abundant. The measurement of the water temperature during the mass occurrence of these species revealed, that Limnothrix redeckei dominated at 180C and Planktothrix agardhii at 200C.