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


vitality

Population status and variation of the rare species Dactylorhiza viridis (L.) R. M. Bateman, Pridgeon and 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.

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.

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.

Vitality Structure and Ontogenetic Strategy of DeLPHINIUM litwinowii (Ranunculaceae)

The article presents the results of a study of the vitality structure of four Delphinium litwinowii Sambuk coenopopulations from the Penza, Tambov and Voronezh regions in the period from 2017 to 2018. The most northern coenopopulation from Penza region in 2017 showed the strongest vitality, while the weakest was the Voronezh’ coenopopula- tion, located to the south, near the village of Vladimirovka.

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.