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

возрастная структура

Age and vitality structure of natural and reintroduced populations of Calophaca wolgarica

The results of the analysis of ontogenetic and vitality structure of Сalophaca wolgarica (L. fi l.) DC. – a rare relict plant species, a paleoendemic to South-Eastern Europe – are presented. As part of the monitoring of the condition of this species’ populations, 21 natural populations on the territories of Volgograd and Rostov regions, the Republic of Kalmykia, Stavropol Krai, as well as fi ve reintroduced populations on the territory of Saratov region were studied in 2024. The ontogenetic conditions of the plants were determined.

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.

Влияние эколого-ценотических условий на плотность и возрастную структуру ценопопуляции HYPERICUM PERFORATUM L. в Саратовской области

Были отмечены два типа биоморф – явнополицентрическая и
моноцентрическая. Плотность особей зависит от эколого-цено-
тических условий местообитаний и погодных условий. Она уве-
личивается в ряду: залежи – низовые луга – опушки и поляны
– степи. Для H. perforatum характерен левосторонний базовый
возрастной спектр с максимумом на виргинильных особях и зо-
ной базового спектра с двумя пиками: большим, приходящимся
на виргинильные особи, и малым – на взрослые генеративные.

Age Structure of Coppice Tree Stands of Upland Oak Forests of the Southern Rart of Privolzhskaya Vozvyshennost’

The article discusses the dynamics of the age structure of coppice tree stands of upland oak-groves of the southern part of Privolzhskaya Vozvyshennost’. Data is provided about fifteen sample plots which were laid in three forest areas of the Saratov region in the most common types of forest conditions (C1 , C1-2 and D1 ). Age was determined for all trees on the sample plot by the cores taken by age borer at the root collar.