Vol 109, No 6 (2024)

The object of this study is a characteristic subshrub of Khakasia, Ziziphora clinopodioides (Lamiaceae). The study of functional traits and the structure of the Z. clinopodioides populations at the eastern limit of its distribution (Republic of Khakasia) has been carried out for the first time. The materials were collected in 2022–2023 in true and meadow steppes of the forest-steppe belt. Environmental factors influencing functional traits and the ratio of individuals of different ontogenetic states have been identified. It has been established that disturbed steppes on sandy soils with the presence of stones and low moisture represent the ecological optimum for this species. Under these conditions, the indices of most of the studied functional traits (the number of vegetative shoots per 1 composite skeletal axis, the number of generative shoots with paracladia, the number of paracladia, the number of flowers in paracladia, the number of flowers in the main inflorescence) reach the highest values. In undisturbed steppes on sandy loam soils with moderate moisture, Z. clinopodioides is in unfavorable conditions, and develops individuals with minimal values of functional traits. All the studied populations are normal, complete or incomplete. Left-sided and bimodal ontogenetic spectra are formed in disturbed steppes on sandy soils with the presence of stones and low moisture; in the undisturbed steppe on sandy loam soil with moderate moisture, the spectrum type is bimodal. The density of individuals depends on the degree of soding in the community and anthropogenic load. With an increase in the total projective cover and in the absence of anthropogenic impact, the density of individuals decreases. The causes of restructuring of functional characters and changes in the ontogenetic spectrum of populations of Z. clinopodioides under the influence of various environmental factors at the range border are discussed.

On Middle-Russian Upland, despite its low paludification, mires are formed on different elements of the relief, differ in their water-mineral regime and vegetation structure. Horizontal structure of the vegetation cover of mire ecosystems, as well as their cenotic diversity, remain poorly studied. However, these features are important for the typology of mires and can also be used in the organization of monitoring of mire ecosystems. The main purpose of this study is to identify the features of the horizontal structure of vegetation and to visualize the phytocenotic diversity of different types of mires using the cartographic method. The objects were 14 model mires located on different relief elements in the northern part of the Middle-Russian Upland.

The conducted studies have revealed the cenotic diversity of the most common and specific types of mires in the northern part of the Middle-Russian Upland. Geobotanical maps were compiled for each mire. The maps of the model mires show 31 mapped units at the rank of association (29), formation (1) and unranked community (1). The identified syntaxons belong to woody, woody-moss, shrubby, hydrophilic-grass and hydrophilic-moss types of mire vegetation, which accounts for 63% of the cenotic diversity of the mires of the Middle-Russian Upland. The vegetation structure is often heterogeneous and heterotrophic, combining both eutrophic and meso- and oligotrophic communities, less often it is homogeneous.

The watershed mires in karst-suffusion depressions are characterized by the largest number of distinguished taxa of vegetation and a complex horizontal structure of vegetation. The vegetation of mires formed in suffusion depressions on terraces and slopes of watersheds overlain by sandstone and moraine deposits is less diverse. Among these mires, pine-sphagnum ones are unique to the region because they are located at the southern limit of their distribution. Such mires are characterized by a homogeneous oligotrophic or heterogeneous homotrophic oligotrophic vegetation structure.

The floodplain and ravine mires are represented only by an eutrophic group of types. Often the vegetation structure of such mires is homogeneous eutrophic, heterogeneity is ensured by changing the moisture regime or is a result of anthropogenic impact.

Trioecy is here described for the first time in the perennial herbaceous polycarpic Ranunculus auricomus L. (goldilocks buttercup) in the Moscow Region. The study has shown that R. auricomus produces three types of flowers, differing in the structure of both the androecium and gynoecium: perfect flowers (with fertile stamens and carpels), pistillate flowers (complete absence of stamens), and staminate flowers (with fertile stamens and reduced nonfunctional carpels). The perfect flowers and their parts are larger than those of the staminate and pistillate flowers. The seven studied populations included five types of plants, forming: 1) perfect flowers (76.9–80.8% of the total number of generative plants); 2) staminate flowers (2.8–3.9%); 3) pistillate flowers (1.0–3.9%); 4) perfect and staminate flowers (10.8–15.9%); 5) perfect and pistillate flowers (1.0–3.0%). Over the five years of observations (2019–2023), plants of different sexual forms did not change the sex of flowers, and the sex ratio in the populations remained stable, with minor fluctuations.

Nitella hyalina and Coleochaete nitellarum were found for the first time in the Siberia. Nitella wahlbergiana, a new species record for Altai Territory, was spotted in one of the southernmost localities of the species distribution range. All species were growing together with Chara braunii, C. virgata and Nitella syncarpa, rare species in Siberia. This association of rare species allowed recognition of Kolyvanskoe Lake as one of important plant areas for charophytes in North Asia.

For the first time, Inula aucheriana DC. is reported for the flora of Azerbaijan. Information is provided on its location in this territory, as well as on its distribution in the Caucasus and adjacent territories.