The Environment-Forming Role of Endemic Species in Calciphilous Communities of the Southern Central Russian Upland

摘要

The territory of chalk deposits in the south of Russia has always been of interest to researches due to its specific geographic features, historical and geological past, the presence of unique natural complexes with chalk outcrops, and floristic diversity (Taliev, 1905; Kozo-Polyanskii, 1931). Primary successions in the vegetation of this region manifest themselves in a specific form. This is why a more comprehensive study of soil nutrient regime, interactions of plants and substrate, and problems of nutrient intake by plants and their accumulation in the phytomass can be of scientific and practical importance (Semenova-Tyan-Shanskaya, 1954; Grigor'evskaya, 2003). We assessed the environment-forming activity of calciphilous plants dominating at different stages of primary succession during the formation of plant communities on chalk outcrops. In addition, we studied changes in some physical and chemical properties of chalky substrates in the root zone of the dominant plants in comparison with soil in other parts of the community. We determined concentrations of main ash elements in the phytomass of five species of obligate cal-ciphytes endemic to the southern part of the Central Russian Upland (Matthiola fragrans, Androsace koso-poljanskii, Artemisia hololeuca, Scrophularia cretacea, and Hyssopus cretaceus) and of Stipa capillata, the dominant species of climax communities developing on the chalky substrate.