Asplenietea trichomanis; petrophytes; chasmophytes; alpine belt; syntaxonomy; Tajikistan; Kyrgyzstan

This paper presents the results of research conducted on chasmophytic vegetation occurring within the alpine belt (approx. 1,850–4,000 m a.s.l.) in the eastern part of Middle Asia. We specifically focused on the diversity and syntaxonomy of rock vegetation as well as on environmental variables determining its distribution. Altogether, 242 relevés were sampled in rock fissures, ledges, and clefts during field surveys conducted in 2013–2019. The size of each recorded vegetation plot was 1 m2. Five main groups of chasmophytic vegetation were distinguished in the studied area. Each group was confined to a specific combination of substrate type and climatic conditions. Altogether, 16 specific plant communities representing chasmophytic vegetation were defined in the study area. For each community diagnostic, constant and dominant species as well as its taxonomic composition and habitat characteristics are given.