THE DEMOGRAPHIC STRUCTURE OF POPULATIONS <i>OXYTROPIS SPICATA</i> (PALL.) O. ET B. FEDTSCH. (FABACEAE) IN SAMARA REGION

Abstract

This article presents the main results of years of research demographic characteristics of natural coenopopulations of rare species in Samara flora Oxytropis spicata (Pall.) O. et B. Fedtsch. (Fabaceae). This representative of the local steppe flora included in lists of protected region with the status of rarity (3/A) - an extremely rare species, drastically reducing their numbers. Studies of species population conducted by us in the years 2000-2013 on the territory of Samara High Zavolzhje in seven points. In the surveyed habitats there are small clusters of individuals. In ontogenetic specter populations lead generative individuals, have a long existence in this period of ontogenesis. The largest share of the population is characterized by a generative individuals to Sernovodsk Sheehan and Vysokaja gora (Sergievsk area of Samara region). Until-generative individuals in the populations studied are mainly represented by virginal instances. Duration stages Until-generative period ranges from a few days to a few weeks, the number of surviving seedlings small. Indices restoration and replacement of individuals in populations have high values. Population dynamics ща Oxytropis is fluctuating character. Often, however, there is a gradual decline in the proportion of mature generative individuals during their transition to a later state of ontogeny, which leads to aging populations and causes loss of species phytocenoses. It is noted that the features of ontogenesis and the demographic structure of populations of O. spicata indicate the need for further protection of the species in the region and changes conservation status in the Red Book of Samara region (3/B - a very rare species, gradually reducing the number).