Экология

The article deals with the stages of recreational digression of diff erent biogeocenoses in the Shirokovsky district forestry of the National Park “Buzuluksky Bor” and the peculiarities of radial growth of the common pine as a dominant stand. The aim of the work was to analyze the comparative response of the common pine trees in the zone of active recreation and in undisturbed areas. The presence or absence of undergrowth, understorey, projective cover and dominance of indicator plants were noted.

The paper presents the results of studying the adventive component of the seed bank of the Oak Mane Island of the Volga River Valley in the vicinity of the city of Saratov. Seeds of 12 species of adventitious plants were registered in the seed bank of the studied forest communities. All identifi ed seeds belong to plant species belonging to one department of Magnoliophyta, 8 families and 12 genera. The Asteraceae family plays a leading role in the taxonomic spectrum of adventitious seed bank species (42%).

The distribution of cicadas in the Khabarovskii Krai has been studied very poorly, in contrast to the Amurskaya Oblast’ and Primorskii Krai. Ledra auditura (Ledridae) (also recorded from the eastern part of Zabaikal’skii Krai, the Argun River basin), Glossocratus foveolatus (Cicadellidae), Eoscartopsis assimilis (Cercopidae), Taihorina geisha (Machaerotidae), Cicadetta yezoensis (Cicadidae), Delphax maritima (Delphacidae), Mysidioides sapporensis, Losbanosia hibarensis, Zoraida albicans, Z.

The eff ects of natural factors (temperatures +34°C and +20°C) and anthropogenic xenobiotics (1,2,4-TriH; 1-(CH3 SO2 )-1H-1,2,4-Tri; 4-(PhSO2 )-4H-1,2,4-Tri; 4-(TolSO2 )-4H-1,2,4-Tri) on watercress Lepidium sativum L. was studied. For this, 4 series of experiments were carried out. In the fi rst two series, the eff ect of concentrations was studied: 0.001, 0.01, 0.1 mg/ml during germination at diff erent temperatures for three days.

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 article refl ects data on year-round studies of the urban mallard population in Saratov, allowing the assessment of the condition and the study of the factors infl uencing its formation. An estimate of the mallard population in the winter periods of 2020–2023 is presented. It is shown that the number negatively correlates with frosts and precipitation, and there is a statistically signifi cant positive relationship between the number of people feeding ducks and the number of mallards.