Floristic diversity and threats factors to floristic diversity of the left bank of the Danube and the network of canals of suburban settlements of Belgrade and

The paper presents the floristic diversity of the left bank of the Danube and the canal network of Krnjaca and Borca settlements, as well as the factors that endanger it. 216 autochthonous and allochthonous plant species were recorded in the investigated area. A large number of invasive plant species have been observed that spread rapidly and easily forming stable populations that displace native plants. Some of them are: Amorpha fruticosa L., Robinia pseudoacacia L., Ailanthus altissima (Mill.) Swingle, Asclepias syriaca L., Ambrosia artemisiifolia L. and others. The presence of 6 species that are rare and endangered in Serbia is especially significant, as well as 5 relict species. During the investigation, the factors which influence on natural habitats degradation and the reduction of autochthonous floristic diversity were identified. Accordingly, measures for protection and preservation of autochthonous floristic diversity are recommended.