Syntaxonomy of steppe depression vegetation of Ukraine

Aims : To revise the syntaxonomy of vegetation steppe depressions ( pody ), in particular (1) to identify associations and reveal their environmental, structural compositional peculiarities; (2) assign higher syntaxa; (3) correct nomenclatural aspects according ICPN. Study area Steppe zone Ukraine, Left-Bank Lower Dnieper basin. Methods 641 relevés were included final analysis PCOrd program integrated into Juice software. Two expert systems (EVC EUNIS-ESy) used classes EUNIS units. Results The resulted nine clusters, which interpreted as Festuco-Brometea (two units), Molinio-Arrhenatheretea (three Iso?to-Nanojuncetea units) one derivate community Festuco-Puccinellietea . Detailed characteristics species composition, structure, distribution, environmental conditions are provided for each unit. According DCA ordination, leading factors syntaxa differentiation soil moisture fluctuating water level. Conclusions We could clarify placement depression system syntaxonomic units Europe. previously described rank alliance Myosuro-Beckmannion eruciformis suballiance Galio ruthenici-Caricenion praecocis six validated. two subassociations a new science. Taxonomic references Euro+Med PlantBase (https://www.emplantbase.org), except Mosyakin Fedoronchuk (1999) Phlomis scythica Klokov & Des.-Shost. Tulipa Zoz. Syntaxonomic Mucina et al. (2016) from class level; Dubyna (2019) associations. Abbreviations = Detrended Correspondence Analysis; DES Didukh Ecological Scales; European Nature Information System; EVC EuroVegChecklist; GIVD Global Index Vegetation-Plot Databases; ICPN International Code Phytosociological Nomenclature.