The Petrophytic Steppes of the Urals: Diversity and Ecological Drivers

The diversity and main compositional patterns of the petrophytic steppes of the Urals were studied. Two questions were considered in detail: (i) How rich is the phytocoenotic diversity of the petrophytic steppes? and (ii) What kind of ecological drivers determine its differentiation? A dataset of 1,025 relevés was compiled,representing communities of different climatic and geological conditions. Using formalized classification (TWINSPAN algorithm), eight vegetation types on the petrophytic steppes were defined. DCA-ordination was used to determine the main ecological drivers (both climatic and edaphic) of plant communities' diversity. Among them are mean annual temperature and precipitation, aridity, rockiness and local habitat moisture. The interaction of different ecological and geographical factors leads to high levels of floristic and coenotic diversity of vegetation in dry rocky habitats. Keywords: petrophytic steppes, ecological drivers, ordination, Southern Ural