Syntaxonomy of the xero-mesophytic oak forests in the Republic of Tatarstan (Eastern Europe)

Aims : To develop a syntaxonomic classification of the xero-mesophytic broad-leaved oak forests Republic Tatarstan with preliminary analysis their unique ecological features. Study area The (European part Russian Federation). Methods A total 91 relevés were processed. Most them (73.6%) sampled in during 2016 and 2017, remaining ones (26.4%) historical published data. They classified by means modified TWINSPAN algorithm using inertia as heterogeneity measure. Diagnostic, constant, dominant species identified analytical tools JUICE 7.0 program. Results study assigned to four clusters. We describe two new associations: Astragalo ciceri-Quercetum roboris ass. nova Sanguisorbo officinalis-Quercetum nova. classify within class Quercetea pubescentis . Conclusions Our is first attempt thermophilous Braun-Blanquet system. Taxonomic reference Czerepanov (1995). Syntaxonomic Mucina et al. (2016) unless stated otherwise text. Abbreviations GIVD = Global Index Vegetation-Plot Databases; NMDS Non-metric multidimensional scaling.