THE URBAN FLORA OF PODGORICA (MONTENEGRO, SE EUROPE): ANNOTATED CHECKLIST, DISTRIBUTION ATLAS, HABITATS AND LIFE-FORMS, TAXONOMIC, PHYTOGEOGRAPHICAL AND ECOLOGICAL ANALYSIS

Abstract

The paper presents a taxonomic, ecological and phytogeographical study of the native and alien flora of the urban area of Podgorica (Capital of Montenegro, SE Europe). The surveyed terrain extends over 86 km2, and apart from the urban it also entails the peri-urban zone. The checklist of vascular plants of the urban area includes1222 species and subspecies from 561 genera and 121 families which represents a little over a third of the total flora of Montenegro. The richness and diversity of the city’s flora are caused by the local geomorphology and climatic conditions of the area, the high diversity of habitats with different anthropogenic impact and the increased immigration of plants from the surrounding ecosystems. Concerning the distribution of the species number by quadrant in the city area of Podgorica ther is no gradient between growing number of species and distance from the urban core. However, if the distribution of the number of taxa per habitat is taken into consideration, it is clear that the homogeneity of habitats and the increase in the urbanisation leads to decline of the number of wild growing taxa. The families represented by the highest number of taxa are Poaceae (11.5%), Asteraceae (11.2%) and Fabaceae (9.2%). while the genera represented most are Trifolium (2.1%), Euphorbia (1.4%), Carex, Ranunculus and Bromus (1.3 each%), Veronica (1.2%), Allium (1.1%), Vicia and Lathyrus (1% each). Apart from the expected high presence of synanthropic, ruderal and ruderal-segetal taxa, the flora of Podgorica is characterised by a significant number of typical urbanophobes. Comparing to the flora of selected European cities (Zurich, Vienna, Rome, Patras and Thessaloniki), Podgorica showed the biggest similarity with Rome (Sørensen’s quotient of similarity (Q/S)= 69.4). The general life form spectrum has therophytic-hemicryptophytic character, which, on one hand, reflects the climatic conditions and on the other the intensive urbanisation of the surveyed area. Like in the spectrum of other Mediterranean cities, the participation of the geophytes is relatively high (11.7%). Conserning phenology, Podgorica is a city in which no interruption of vegetation growth and something is always in flower. The majority of plants flower in May, the smallest number flowers in December. Regarding the ecological temperature index, dominating in the city area are thermophilic plants (T7 and T8), an indication of the Mediterranean character of the city area. Prevalent in terms of the light index are heliophyllic plants (L7 and L8), conditioned by exposure of the terrain to sunlight, as well as by the degradation of the primary forest cover and the domination of open and sunny habitats. Dominant in terms of soil reaction are neutrophilic and neutro-basophilic species (R5 and R7), and in terms of nutrients oligotrophic plants (N2 and N3). Dominating in terms of the humidity index are H3 and H4 plants, as expected considering the climatic conditions and hydrography of the area. The phytogeographic spectrum of Podgorica fits into the general spectrum of South European cities and is characterised by the prevailing presence of Mediterranean species s.l. (39.7%). The participation of aliens is relatively small (14.1%), probably due to the short history of the settlement and the poorly developed transportation and trading networks. Dominant among aliens are taxa of Asteraceae (15.7%) and plants of Asian (43%) and North American origin (23.2%). The most aggressive aliens in the city area are Ailanthus altissima, Artemisia annua, A. verlotiorum, Bidens subalternans, Broussonetia papyrifera, taxa of the genus Erigeron, Symphyotrichum squamatum and Xanthium orientale subsp. italicum.The comparative analysis of selected habitat types in the area of Podgorica showed that two habitat types are distinguished by prominent floristic richness: meadows (46.1%) and dikes along railroad tracks (32.1%). Due to constant degradation and loss of habitat in the strict urban zone of Podgorica which on one hand causes the loss of native flora, and on the other facilitates the expansion of the alien flora, we expect the effect of the biotic homogenisation to be noticeable in the area of Podgorica.The allergenic flora of Podgorica includes 253 taxa of wild vascular plants whose pollen has been grouped into three categories: woody plants pollen (32 taxa), weed pollen (76 taxa) and grass pollen (145). Tree pollen is present from February to April, while weed and grass pollen from April to October.