The distribution of Salvinia natans (L.) All. in the Odra and the Oława River valleys in Wrocław area (Poland)

The data presented in this paper concern the occurrence of Salvinia natans (L.) All. in Wrocław area. Field research was conducted in the vegetation season (June-September) between 2013 and 2017 in water bodies (natural and artificial), in the main river beds of the Oława and the Odra Rivers and in the Odra canals in Wrocław. The study provided 32 S. natans locations in the city area. The studied species occurred in various plant communities accompanied by numerous species which were also under protection, increasing the ecological value of the habitats. Additionally, a stable S. natans site was confirmed by the study in a location where aquatic fern had previously been recorded in Wrocław. The research indicates numerous populations of the species along the Odra and the Oława and in many old river beds and artificial water bodies in Wrocław and the results confirm the visible trend of a growing number of S. natans sites in all of Poland.