The vascular and bryophyte flora of the Nature Monument Vrelo Une

During growing seasons 2018-2019 and in winter 2021, the flora of vascular plants and bryophytes of the Nature Monument Vrelo Une in southern Croatia was studied. The previous floristic data available for this area, covering 9.58 ha, are sparse, and this study recorded 219 taxa of vascular plants from 59 families. The species-richest families are Compositae (10.5%), Fabaceae (8.2%), Poaceae (7.8%), and Lamiaceae (6.4%). Additionally, 64 bryophyte species (14 liverworts and 50 mosses) were recorded. The spectrum of biogeographic elements of vascular plants places the study area in the Euro-Siberian region, at the meeting point of two vegetation sub-zones within the European broadleaf deciduous forests zone – thermophilic, sub-Mediterranean forests of the class Quercetea pubescentis and mesic forests of the class Carpino-Fagetea sylvaticae. The species of the South-eastern European and Illyrian elements give a local distinctiveness to the flora. The biogeographic elements of bryophytes are less sensitive but reflect the same biogeographical pattern. Since most of the researched area is covered by forests and thickets, the largest number of species of vascular plants are associated with these particular habitats, while rocks and aquatic habitats are the most important for bryophyte diversity. In terms of the IUCN categories, four species are classified as near threatened, three as least concern and three as data deficient. Invasive species have not been recorded