The assessment of the spatial ontogenetic structure of the coenopopulation <i>Oxytropis floribunda</i> (Pall.) DC. in undisturbed coenoses (on the territory of the Samara Region)

Abstract

Data on the peculiarities of rare plants coenotic populations organization in petrophytic steppes make a certain contribution to the development of theoretical issues of phytocoenology, bioecology and nature protection. Coenopopulations of Oxytropis floribunda (Pall.) DC. are monitored on the territory of the Samara Region (the natural monument Sernovodnyy Shikhan) in the course of the work. Population ontogenetic methods have been used, including methods of spatial statistics. The coenopopulation of the species has been studied in the Stipa pennata Oxytropis floribunda community without any apparent anthropogenic load. It has been found that the total number of individuals of O. floribunda in the studied coenopopulation was 81 individuals, with a density of 6 individuals per 1 m. The phytogenic field strength coefficient is 0,06. The studied community is dominated by the pregenerative age states of O. floribunda. The coenopopulation of O. floribunda is generally characterized by a contagious type of spatial structure with the formation of aggregations of 0,41,2 m in size. The Ripley function graph for pregenerative plants has also showed the presence of clustering zones that occurs due to seed germination near the mother plants of the studied representative. Generative individuals of O. floribunda in the plant community are located randomly, which indicates favorable conditions for the growth of the species in this area.