Rybak, AndrzejMessyasz, Beata2011-06-212011-06-212011-03Chrońmy Przyr. Ojcz. 67 (2): 182–188, 20110009-6172http://hdl.handle.net/10593/1106The research site was located on the flow water reservoir in Poznań (Wielkopolska). The place of U. flexuosa subsp pilifera (Kütz.) Blinding 1963 appearing on the studied area is the 4th inland site of this species in Poland (ATPOL BD09) (Fig. 1). In 2009 the new locality of Ulva flexuosa subsp. pilifera was found in Malta Lake in Poznań City (Fig. 2). Presence of considerable biomass of U. flexuosa subsp pilifera in this freshwater ecosystem was pointed out to the great fertility of the examined water reservoir. The trophic state at the site with U. flexuosa subsp pilifera can result from the fact of the permanent inflow of urban pollutants from Swarzędz, flowing with Cybina river to the examined water reservoir.plUlvaEnteromorphafreshwater UlvaMacroalgaegreen tidesmarine algaefreshwater EnteromorphastreamMalta LakeMalta ReservoirUlva in lakeUlva in riverUlvaceaeChlorophytaUlva flexuosa subsp. piliferaUlva flexuosamacroalgae matsmaty makroglonowezbiornik wodnyPoznańbłonica oszczepowatabłonicaulwa słodkowodnabłonicowateArtykuł