Soil-Geomorphic Microzones and Calciphilous Vegetation of Chalk Landscapes in the Kamensky and Kalacheyevsky Districts of the Voronezh Region

Abstract

The purpose of the work is to identify and analyze the relationship between the soil-geomorphic microzones of chalk landscapes and the distribution of calciphilous plant communities within the Kamensky and Kalacheyevsky Districts of the Voronezh Region. Materials and methods. The research materials consisted of coupled soil-geobotanical studies of key areas of chalk slopes. Comparative geographical, soil-morphological, geobotanical, fl oristic, and edaphic approaches and methods were used. Results and discussion. It has been found that in the Kamensky District, the clearly expressed microzonality of the slope profi le determines a regular succession of soils and plant communities: from typical sod-carbonate soils of upper-slope positions to their eroded variants in the transit part and sod-alluvial soils in the accumulative footslope microzone. At the same time, the maximum values of species richness and projective cover in plant communities are characteristic of the footslope microzone, while the minimum values are observed in the mid-slope erosional areas. However, it is precisely on the mid-slope areas that a high proportion of calciphilous fl ora elements is observed. In the Kalacheyevsky District, the structure of communities is determined by the combination of remnant relief and light carbonate soils on sandy deposits: sparse thyme–Artemisia salsoloides communities form on the slope, whereas denser thyme–Artemisia hololeuca communities occur at the footslope. Conclusion. It has been shown that soil-geomorphic conditions, the carbonate nature of the substrate, the thickness of the fi ne-earth, and the degree of erosional disturbance of soils on the slope profi le are the leading factors in the spatial diff erentiation of calciphilous vegetation.