PL
W pracy przedstawiono nowe, dotychczas nieznane stanowisko rukwi płonnej Nasturtium ×sterile (Airy Shaw) Oefelein., które zostało stwierdzone w sztucznym kanale koło Trzcianki na Pojezierzu Wałeckim. Jest to prawdopodobnie pierwsze odnalezione stanowisko tego gatunku w Polsce.
EN
A new, previously unknown, occurrence site of Nasturtium ×sterile (Airy Shaw) Oefelein. was found in Poland in July 2008, and then again in August 2009. It is situated in an artificial channel, a tributary of the Wrzącka Toń River, around 2 km east of the Biała village (16°32′E, 53°02′N), the commune of Trzcianka, the district of Czarnków-Trzcianka, the Wielkopolska province. The maximum width of the channel is 3 m, the water is transparent and the flow is slow. During both years of observations, the phytocoenosis dominated by Nasturtium ×sterile formed large thick patches floating on the water surface near the rushes. A few specimens were observed in the rush vegetation located close to the channel bank. Both blooming and fruiting specimens were observed. Floods, water contamination and maintenance works along the channel bank or in the channel bed pose the greatest threats to the population. Prevention of such threats should be a sufficient measure to support gradual regeneration of the population