Synphytoindication assessment of the steppe part of vegetation of the Syniukha River valley (the Southern Bug catchment area, Ukraine)

Abstract

The article describes vegetation diversity patterns of the steppe part of the Synyukha River valley (the Southern Bug catchment area, southern Ukraine), which is represented by 20 alliances, 14 orders, and 13 classes. It has been found that general differentiation of the vegetation is most influenced by edaphic factors (soil moisture, nitrogen content, and aeration), and somewhat less – by damping variability, salinity and acidity regime. The vegetation ecofactors of the alliances Festucion valesiacae, Berberidion vulgaris, Prunion spinosae, and Prunion fruticosae best correspond to the background ecological indicators of the steppe part of the Syniukha River basin. The high cenotic diversity and specific vegetation of the granite outcrops were observed. Based on the calculations, we demonstrated that the steppe part of the Syniukha River catchment area is the southern limit of distribution of Carpinion betuli forests due to the conditions close to the limits of their ecological optimum.