Although urbanization is recognized as a major driver of biodiversity change globally, its impact on the evolutionary history of flora in arid regions remains understudied. This study provides a comparative analysis of the phylogenetic structure of the floras of three major cities in Uzbekistan Tashkent, Fergana, and Bukhara, located in different climatic zones. Species richness, phylogenetic diversity (Faith’s PD), and phylogenetic structure indices (MPD and SES.MPD) were employed in the study. The results indicated that while urbanization leads to an increase in species diversity across all cities due to alien species, the phylogenetic structure differs sharply depending on the regional climate. In the temperate cities of Tashkent and Fergana, the urban environment was observed to act as a harsh “ecological filter,” resulting in strong phylogenetic clustering among alien species. In contrast, a distinct mechanism the “Phylogenetic Release” phenomenon was identified in the arid city of Bukhara. Here, anthropogenic maintenance mitigates natural stress factors, allowing the urban environment to act as a “facilitator” and enabling the persistence of evolutionarily diverse species. This study demonstrates that urbanization in arid regions can alter the evolutionary dynamics of flora and highlights the necessity of considering local climatic characteristics when creating sustainable urban ecosystems.
JURAEV et al. (Tue,) studied this question.