Izvestiya of Saratov University.
ISSN 1816-9775 (Print)
ISSN 2541-8971 (Online)


ценопопуляция

Ontogenetic and vitality structure of Globularia bisnagarica L. cenopopulations in the Middle and Lower Volga regions

The article presents the results of studying the ontogenetic and vitality structure of 13 cenopopulations of Globularia bisnagarica from the Middle and Lower Volga region. The assessment of the ontogenetic structure was carried out by constructing and analyzing the ontogenetic spectra of each of the studied cenopopulations, as well as the basic ontogenetic spectrum, followed by determining the type of cenopopulations according to the “delta-omega” criterion.

The Variability of Some Morphological Parameters Calophaca Wolgarica in the Populations of the Volgograd Region

It is shown that habitat conditions have a strong influence on the shape and vitality of the state of the individual Calophaca wolgarica. The most favorable conditions for the growth of Calophaca wolgarica in the Volgograd region are aligned sites with non-light-chestnut fairly rich soils in shrub-grass and couch-grass communities on the edges of the belts, on which there is no mowing and minimal grazing.

The State of the Cenopopulation Delphinium Pubiflorum (Dc.) Turcz. Ex Huth in Tatishevskiy District of the Saratov Region

Delphinium pubiflorum grows sparsely in the meadow-steppe forbgrass-shrub community on carbonate chernozem fairly rich soil. Habitat conditions correspond to moderately variable meadow-steppe hydration. The spatial structure of populations of non-uniform: there are a multitude of plants and detached instances; population density was approximately 7–8 plants per 100 m2.

About the Biology of the Invasive Species Hordeum jubatum L. in Bashkir Trans-Urals

The results of researches of 7 coenopopulations of North American invasivespeciesHordeumjubatumL.(Poaceae)inthe Trans-Urals of the Republic of Bashkortostan. Hordeum jubatum spreads on the steppe zone of the region. It dominates over other plants and it is share of participation in the community is 45,5–60,5%. The density of grass invasive species – 9–18 plants per 1 m2.Each plant produces 35 to 68 shoots, on average, is more than 600 shoots per 1 m2. The biomass of the type is no more than 0.25 kg/m2. Seed production is 39–54 pcs.

Ecological and Phytocenological Characteristics of Associations of Delphinium Pubiflorum

 posed to any significant anthropogenic impact due to the sufficient remoteness and inaccessibility of habitats. The area occupied by the associations does not exceed 400 m2. The total projective cover amounts to 90–100 %. The associations are quite rich and relatively even in terms of species composition. The number of species ranges from 48 to 72, and the most homogeneous association is the one in Krasnoarmeysky raion which also occupies the smallest territory. The number of species registered in one and the same association varies from one year to the next.

The Influence of Ecological Factors on Variability of Morphometric Parameters of Rare Species Iris pumila L.

The study of intraspecific variability of rare plants allows to estimate the level of phenotypical variability, to establish borders of populations, to characterize microevolutionary processes, to reveal the ecological factors influencing formation of structure of populations that finally promotes preservation of a gene pool of rare species. Work purpose: studying of intraspecific variability of rare species Iris pumila L. in the south of the Cis-Urals of Bashkortostan Republic.

Ontogenetic Structure and Population Status of the Relict Species of Hedysarum gmelinii Ledeb. in the Cis-Urals Republic of Bashkortostan

The results of studying the ontogenetic structure of coenopopulations of the relict species Hedysarum gmelinii Ledeb. in the Bashkortostan of Republic are presented. The investigated cenopopulations growing on slopes of different exposure, with a slope of 35°, is the main type of vegetation – Helictotrichon desertorum–Stipa korshinskyi petrophyte steppe, anthropogenic load is low or medium. The overall density of the coenopopulations of H. gmelinii varies from 1,7 to 12,2 ind./m2, an effective density from 1,5 to 4,6 ind./m2.

Ontogenetic Tactics and Strategies of Oxycoccus palustris Pers. Survival in Boggy Ecosystems of Taiga Zones (Kirov Region)

The paper presents the results of studies of Oxycoccus palustris Pers. ontogenetic tactics and strategies expressed in various types of boggy phytocoenoses of the taiga zone in the Kirov region. The morphometric variability analyses of O. palustris in studied coenopopulations showed that most of parameters vary significantly. According to vitality index (IVC) the most favourable conditions are presented in mesotrophic cotton-grass sphagnum bog and oligotrophic sphagnum bog where the index was maximum – 1.04.

Some Features of the Biology of Invasive Species Conyza canadensis (L.) Cronq. in the Abkhazia Republic

The invasion of aggressive adventive plants in the territory of the Abkhazia Republic has a significant impact on the loss of biodiversity and the imbalance of ecosystems. In this regard, monitoring of the invasive component of flora is an urgent task. The aim of work was to study the biological features of invasive species Conyza canadensis under the conditions of Abkhazia. The research objectives included the study of morphometric parameters of the species and their variability.

Population status and variation of the rare species Dactylorhiza viridis (L.) R. M. Bateman, Pridgeon & M. W. Chase (Orchidaceae) under anthropogenic load conditions in the meadow phytocenoses of the Central Caucasus

We studied the variation of morphological characters, ontogenetic structure and vitality of seven cenopopulations of Dactylorhiza viridis (L.) R. M. Bateman, Pridgeon & M. W. Chase within the Kabardino-Balkar Republic in 2015–2019. The studies were conducted in the meadow plant communities under different conditions of anthropogenic load (recreation and grazing). The species presents medium phytocenotic plasticity of morphological characters (I p=36–70%) and high variation of morphological characters (CVх–ср=18,55–45,22%) under changeable conditions of growth.