Vegetation of alpine screes on Bjelašnica Mt. — syntaxonomy and ecology

We analised vegetation of calcareous screes in the alpine belt of Bjelasnica Mt. (Western Balkan) by the Central European phytosociological method. In total, 69 releves were submitted to numerical analysis in R ver. 3.5.2. (UPGMA clustering with chord distance). The obtained cluster dendrogram showed differentiation in nine associations, of which Festuco xanthinae—Valerianetum montanae Trakic et al. ass. nov. and Drypido spinosae—Seslerietum wettsteinii Trakic et al. ass. nov. are new ones. In lower section of the alpine belt we described new subassociation Pseudofumarietum leiospermae helictochloetosum Trakic et al. subass. nov. which raises questions about ecological preferences of the alliance Corydalion ochroleucae. We also neotypified the association Drypidi—Heracleetum orsinii Redžic et al. ex Trakic et al. and made correction for Pseudofumarietum leiospermae Lakusic et Redžic 1991 nom. corr. The observed high diversification of the alpine screes on Bjelasnica Mt. is based upon its ecological heterogeneity and tranzitional position in the Dinarides.