Acta Scientiarum Polonorum
Silvarum Colendarum Ratio et Industria Lignaria

This paper presents the results of the study on the plant cover of the surrounding of the Rusałka Lake in Poznań, conducted on the area of 138.9 ha. The flora of the studied area contains of 314 species of vascular plants, including 76.4% of native species. The vegetation of the studied objects consists of 41 plant communities (including 34 plant associations), representing 8 phytosociological classes. Anthropogenic impact on the flora is shown by a higher number of apophytes (55.4%) compared to spontaneophytes (21%), high share of hemerophilous species (77.4%), which is connected with human activity and high share of alien species (74 species – 23.6%), in which kenophytes (15.9%) are the most numerous, including 19 invasive species. Despite that the studied area is a shelter for woodland flora, which is proved by a high share of species typical for fertile deciduous forests (18.8%) and occurrence of 26 ancient woodland indicator species, as well as the predominance of urbanophobic species (59.2%), over urbanoneutral (30.6%) and urbanophilous (7.3%). The vegetation of the studied object consists of 41 plant communities, including 34 associations. It has been dominated by Galio-Carpinetum, Fraxino-Alnetum and artificial plantations of Pinus sylvestris and Robinia pseudoacacia. Forest plant communities of the studied area show symptoms of a degeneration, manifested in simplifying of the species composition, neophytisation, geranietistation, and lack of diagnostic species. Especially strong degeneration symptoms were recorded in oak-hornbeam forests, ash-alder riparian forests and in pine plantations.