Spatial structure of Globularia bisnagarica L. (Plantaginaceae, Magnoliopsida) coenopopulations

Abstract

The paper presents the results of the spatial distribution analysis of 18 Globularia bisnagarica L. coenopopulations in the Saratov, Samara, Ulyanovsk and Orenburg regions and the Republic of Tatarstan. The analysis was carried out with the Spatstat package of the R environment for statistical computing. The research reveals an aggregation tendency for the G. bisnagarica coenopopulations. It is suggested that this tendency may be attributed to the prevalence of seed reproduction and certain peculiarities of dissemination (barochory) in the studied coenopopulations as well as to the confinement of the species to eroded landforms (slopes of watersheds, gullies, runoff hollows, etc.) characterized by high heterogeneity of environmental conditions. It has been established that the majority of G. bisnagarica coenopopulations grow in heavily or moderately sodded habitats. Nevertheless, in the studied communities, G. bisnagarica occurs abundantly and dominates along with Stipa pennata, Bromus inermis, Salvia nutans, Elytrigia repens, Poa compressa, etc. Finally, the spatial structure of G. bisnagarica coenopopulations is impacted by the interspecific competition in calciphilous phytocenoses under the invasion of eurybiontic steppe grasses.