Phytosociology of Stipa-dominated steppe-like vegetation on the ultramafics of the Central Balkans

Abstract

Despite the fact that dry grassland vegetation on ultramafics has been the object of continuous research in previous centuries, there remains a knowledge gap in regard to the initial stages of vegetation on ultramafic substrates. The Stipadominated dry grasslands of Serbia and Kosovo representing various initial phases in the overgrowth of ultramafic rocks were the object of the present study. A total of 213 relevés were made in different steppe-like Stipa species-dominated grasslands on ultramafics of Serbia including Kosovo, and were then analysed in the context of Balkan dry grassland vegetation of the Festuco-Brometea class. For cluster analyses, new relevés were analysed in order to characterize them floristically and sintaxonomically. For describing associations, we used the concept of “relative fidelity’’ allowing us to find the optimum occurrence of a species within a group of floristically similar communities. The threshold of the phi value was selected at 0.1 for new associations. Four new associations were distinguished: Stachyo scardicae-Stipetum tirsae ass. nov., Euphorbio glabriflorae-Stipetum pulcherrimae ass. nov., Alysso serbici-Stipetum pulcherrimae ass. nov. and Thymo striati-Stipetum mayerii ass. nov.. Relevés dominated by Stipa novakii were asigned to previously described Stipetum novaki Kabaš et D. Lakušić 2013. The first three new associations were assigned to Potentillion visianii, while the latter was assigned to the Centaureo kosaninii-Bromion fibrosi alliance of the Halacsyetalia sentneri order.