Spatial Patterns of Species Diversity in the Saline Vegetation of Central Anatolia, Türkiye

Vegetation on saline soils thrives under extreme conditions. The saline vegetation of Central Anatolia is a key component of the Irano-Anatolian Biodiversity Hotspot, notable for its high habitat and species diversity. However, there has been a lack of quantitative assessments of plant diversity in these areas. To address this gap, this study aims to calculate and compare: 1) local species diversity (alpha diversity) across five vegetation alliances, 2) regional diversity (gamma diversity) for each alliance, and 3) the variation in species diversity within alliances (beta diversity). Data from 101 plots representing five alliances collected from Burdur Lake, Acıgöl, Salt Lake, Seyfe Lake, and Sultansazlığı were compiled from relevant publications. The results showed high species diversity in areas with high variation in salinity or humidity due to ecotone characteristics, at all spatial scales. Notably, diversity was highest in salt steppes (Achilleo wilhelmsii-Artemision santonici) and in slightly-saline summer-dry marshes (Lepidio caespitosi-Limonion iconici and Inulo aucheranae-Elymion salsi). Conversely, diversity was lower in non-saline steppes typical for gypsum soils (Astragalo karamasici-Gypsophilion eriocalysis) and in communities found on hypersaline soils (Salicornion fruticosae). Overall, beta diversity was high, reflecting significant species turnover. These findings numerically support existing literature, which suggests that plant community composition can change drastically over short distances. The results highlight the conservation priority of saline areas with ecotone characteristics.