Human impact on plant communities in urban area assessed with hemeroby grades

Paper presents a scale of hemeroby of 86 plant communities constituting the vegetation cover of Szczecin (northwestern Poland), studied in the years 1999-2002. The applied nine-grade hemeroby scale expresses the anthropogenic transformation of habitats and enables the presentation of the vegetation resilience to human impact. The hemeroby spectrum of the analysed syntaxa differs from one grade in case of highly specialised communities (either semi-natural or synanthropic, like Typhetum latifoliae and Eragrostio-Polygonetum) to six grades - for communities found both on semi-natural and highly modified habitats, usually occupying eutrophic biotopes (like Urtico-Calystegietum and Urtico-Aegopodietum).