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Aims: In this paper we propose the first syntaxonomic classification for the mesophilous scrub vegetation in Tajikistan with some remarks on their environmental variability. Methods: Altogether 120 relevés were sampled using the standard, seven-degree cover-abundance scale of Braun-Blanquet, in 2015-2021. They were classified by the modified TWINSPAN method using the four step interval scale with cutoff levels of 0%, 2%, 5% and 10% and total inertia as a measure of cluster heterogeneity. Diagnostic species were identified using the phi coefficient as a fidelity measure. Detrended Correspondence Analysis (DCA) was used to determine the relationship between the sampled plots, vegetation units and major gradients in species composition. Results: Plant communities known so far as šhiblyak and including xeric and mesophilic shrublands seral or marginal to broad-leaved forests in the nemoral zone of the Irano-Turanian region are described herein. Numerical analyses of vegetation data allowed distinguishing five associations representing the Ranunculo tenuilobi-Cotoneasterion hissarici alliance. The new associations include: Eremuro comosi-Rhuidetum coriariae, Calophacetum grandiflorae, Fraxinetum raibocarpae, Pruno sogdianae-Crataegetum turkestanicae, Aflatunio ulmifoliae-Caraganetum turkestanicae. For the latter association, two habitat variants (with Ferula clematidifolia and Malus sieversii) are proposed. The main factors determining the species composition of the studied vegetation include: elevation, mean annual temperature and sum of annual precipitation. Conclusions: The research results herein presented fill the gap in knowledge about the shrubland vegetation of Tajikistan. Studies in neighbouring countries and a focus on subalpine scrubs in dry habitats are needed to complete the classification of shrubland vegetation of Middle Asia. [ABSTRACT FROM AUTHOR]

Aims: To complete the syntaxonomic scheme for tall-forb vegetation of the montane and alpine belts in the Pamir-Alai and western Tian Shan Mountains in Tajikistan and Kyrgyzstan with some remarks on its environmental predictors. Study area: Middle Asia: Tajikistan and Kyrgyzstan. Methods: A total of 244 relevés were sampled in 2013-2019 using the seven-degree cover-abundance scale of the Braun-Blanquet approach. These were classified with a modified TWINSPAN algorithm with pseudospecies cut-levels 0%, 5% and 25%, and total inertia as a measure of cluster heterogeneity. Diagnostic species were identified using the phi coefficient as a fidelity measure. NMDS was used to explore the relationships between the distinguished groups. Results: Our classification revealed 19 clusters of tall-forb vegetation in Middle Asia. Among others we found forb communities typical for Tian Shan, western Pamir-Alai, forb-scree vegetation of Pamir-Alai, dry tall-forbs and typical forbs of the alpine belt. A total of eight new tall-forb associations and five communities were distinguished. The forb vegetation of Middle Asia has been assigned to the class Prangetea ulopterae Klein. The main factors differentiating the species composition of the researched vegetation are elevation, mean annual temperature, sum of annual precipitation and inclination of the slope. Conclusions: The paper presents the first insight into the comprehensive classification of the alpine forb vegetation in Middle Asia and fosters progress in explaining the relationship of boreo-temperate and Mediterranean-like (Irano-Turanian) vegetation in western Asian and central Asian subregions of the Irano-Turanian phytogeographical region. [ABSTRACT FROM AUTHOR]