Comparison of urban flora in Split, Dubrovnik, and Mostar

Urban flora sampled in the coastal cities of Split and Dubrovnik (Croatia) and in Mostar (Bosnia and Herzegovina) was represented by 325, 243, and 106 vascular plant taxa (species and subspecies), respectively. Similarity coefficients between the flora of Split and Dubrovnik, Split and Mostar, and Dubrovnik and Mostar were, respectively, 41.8, 17.9, and 19.0%. Fifty-one taxa were common among all three cities. The Mediterranean floral element dominated all three, with the families Asteraceae, Poaceae, and Cichoriaceae having the highest number of taxa. According to Raunkiaer's life-form spectrum, therophytes dominated Split (48%), while hemicryptophytes were more common in Dubrovnik (36%) and Mostar (39%). In total, 62 (Split), 41 (Dubrovnik), and 19 (Mostar) taxa of alien (allochthonous, non-native) plants were identified. Most were neophytes originating in the Americas (Split, 65.5% ; Dubrovnik, 73% ; Mostar, 52.6%). The urban flora of Split and Dubrovnik is Mediterranean and, in both quality and quantity, is comparable to that of cities in central and southern Italy. Differences among the three cities may be explained by historical differences in the nature and intensity of human impacts.