Allochthonous plant species in the vegetation of the Great War Island

Abstract

The main aim of the conducted research was to determine the presence of allochthonous plants in the area of the protected natural reserve - The Great War Island. The research was conducted during the vegetation season of 2020. Thirty four allochthonous plant species were recorded and classified into 19 families. Asteraceae (8 species), Fabaceae Poaceae and Sapindaceae (3 species each) had the highest species diversity. Phytogeographic analysis of their primary distribution areas has shown that most belong to the category of floral elements of the "adventitious" areal type. The chorological spectrum is dominated by species of North American origin (58.8%), while in the biological spectrum the most common are therophytes (38.2%). Chronological spectrum analysis has shown the highest prevalence of neophytes (64.7%). Seventeen species have the status of invasive, 16 naturalized, while one species (Morus alba) is characterized as ephemerophyte. The most frequent neophytes on the Great War Island are Acer negundo, Ailanthus altissima, Amorpha fruticosa, Fraxinus pennsylvanica, while among neotophytes, Echinocystis lobata and Symphyotrichum lanceolatus stand out in terms of frequency of occurrence. The geographical position of the Great War Island, due to which it is exposed to periodic floods, high levels of groundwater, strong influence of anthropogenic factors and the biological characteristics of allochthonous species are the main factors enabling them to inhabit this area. Results of this research should be the basis for the development of a strategy for monitoring the condition and planning control measures for the unwanted plant species, in order to protect the indigenous flora. Only careful and responsible management of landscapes of outstanding features such as The Great War Island and taking appropriate preventive measures can prevent the settlement, domestification and further spread of allochthonous plants.