Phytoplankton as an indicator of the current ecological status of the Ob River

The species composition, taxonomic structure, and the dominant complex of algae, and the distribution of phytoplankton abundance in the studied watercourse were identified based on data obtained for phytoplankton from the Ob River (from Tomsk to Salekhard) in summer 2019. Green algae (division Chlorophyta) make up the basis of the phytoplankton abundance in the river. The dominant complex is represented mainly by centric diatoms (genera Aulaсoseira, Cyclotella, Stephanodiscus) and non-heterocyst forms of cyanoprokaryotes (genus Aphanocapsa). The numbers and biomass of phytoplankton gradually decrease downstream of the Ob River; below the confluence of the Irtysh River, the edge effect occurs: increase in the diversity and density of organisms at the boundaries of ecosystems. Compared to the previous studies, the proportion of green and euglena algae, and cyanoprokaryotes in the taxonomic spectrum of phytoplankton increased, the composition of the dominant complex enriched, including due to non-heterocyst forms of cyanoprokaryotes, and the trophic status of the river increased to the category of eutrophic waters.

New discoveries of Geometridae (Lepidoptera) from the extreme southwest of the Russian Far East – result of climate impact?

New founds of 4 species of East Asian Geometridae: Megabiston plumosaria (Leech, 1891), Photoscotosia lucicolens (Butler, 1878), Callabraxas fabiolaria (Oberthür, 1884), and Dysstroma cinereata (Moore, 1867) in the extreme southwest of the Russian Far East are presented and discussed due to the actual distribution and its current trends. From them Ph. lucicolens is recorded from Russia and China (Jilin) for the first time. Identity of specimens of "Photoscotosia atrostrigata" and "Dysstroma cinereata" in Barcode of Life Database is revised to Ph. lucicolens and Paradysstroma corussaria (Oberthür, 1880) respectively. These founds probably indicate northern expansion of ranges of geometrid moth in accordance with the current climatic trend of global warming. Potential harmfulness of M. plumosaria in RFE is assumed. The validity of Dysstroma cinerea cesa Koçak & Kemal, 2001, as a substitute name for Dysstroma cinereata japonica (Heydemann, 1929) is substantiated.

Synanthropization and species diversityof floodplain ecosystems of the Ob-Irtysh basin, Russia

Currently, the phytocenoses of the Irtysh floodplain are experiencing intense anthropogenic pressures due to the intensive development of the oil and gas industry, as well as the urbanization of the territory. This paper focuses on the structure and species composition of the 27 studied areas in the floodplain ecosystems of the Ob-Irtysh basin. As a result of the research, we found 111 species of vascular plants from 33 families in plant communities. The areas belong to meadows and forest vegetation are represented by (1) birch forests (33%), (2) pine forests (10%), (3) fir forests (8%), (4) aspen forests (4%) and (5) associations of meadows (45%). Furthermore, we conducted a comparative analysis of the studied phytocenoses according to the Drude scale. To determine the anthropogenic transformation of the flora and individual plant communities, we determined the synanthropization index (the ratio of synanthropic species to the total number of species). In the synanthropic flora fraction, we distinguished 45 species belonging to 12 families, with the most multispecies being Apiaceae, Scrophulariaceae, Compositeae, Ranunculaceae, Poaceae, Fabaceae, Plantaginaceae. The synanthropization index of the studied phytocenoses ranges from 6.6% to 81.2%. The largest number of synanthropic species occurs in meadow associations, the content of synanthropes is greater than 50%, the structure is becoming more superficial, and the productivity and stability of plant communities are changing. The study of the horizontal structure of grass stands of meadow phytocenoses makes it possible to find the variability of different years, the change of dominant species and the stability of the species composition. Currently, researchers are paying considerable attention to the analysis of the structure of the herbage, since its study is of great theoretical and practical importance in clarifying phytocenotic relations.

Ecological and morphological features of Rhodiola rosea L. in natural populations in the Altai Mountains

The paper presents the results of the comprehensive study of Rhodiola rosea L. in natural populations in the Altai Mountains. The phytocoenotic confinement, demographic structure, and morphological characters of coenopopulations of Rh. rosea were studied in different ecological and coenotic conditions in the Chemal and Kosh-Agach regions of the Republic of Altai. Correlation between the morphometric parameters and their calculated values for the shoot and sex of the studied individuals, as well as environmental factors, was revealed. Rhodiola rosea L. is a valuable medicinal plant used for functional diseases of the central nervous system. At present, the natural reserves and areas of natural growth of the golden root have decreased significantly. The species is included in the Red Data Book of the Russian Federation (2008) and many regional Red Data Books of Siberia. In the Altai Mountains, Rh. rosea is widespread throughout the highlands, where it has occupied a wide range of habitats. The study showed that the highest values of ecological and effective density are characteristic of coenopopulations which are part of various hygrophytic variants of alpine and subalpine miscellaneous herbs with a high total projective cover of the herbaceous layer (CP 1, 2, 3, 4). The lowest values were found for coenopopulations growing in communities with a scarce herbaceous layer or dense shrub layer, and on steep gravelly slopes with crumbling soil and nonuniform moisture distribution (CP 5, 6, 8, 9). The studied coenopopulations are normal, full-membered, or incomplete-membered (some of them lack postgenerative individuals). In terms of the ontogenetic spectra, they are mainly left-sided, with a predominance of young generative individuals (CP 4, 5, 7) or bimodal, with an additional peak for old generative individuals (CP 2, 3, 6, 8). Male and female individuals Rh. rosea differ in many morphometric characters of the generative shoots. In some coenopopulations (CP 2, 3, 6, 9), male and female individuals show multidirectional deviation of characters compared to the totality, which indicates that in different environmental conditions these characters are not only genetically determined but can also be related to the sex of individuals.

New records of Geometridae and Noctuidae (Insecta: Lepidoptera) from Omsk and Novosibirsk Regions of Russia

Nine species of Lepidoptera from the territory of Omsk and Novosibirsk Regions are reported. Four species are new to Omsk Region, among them, Panchrysia ornata (Bremer, 1864), Sympistis campicola Lederer, 1853, Pseudohadena argyllostigma (Varga & Ronkay, 1991), Orthosia cerasi (Fabricius, 1775). Six species are new to Novosibirsk region, among them Eupithecia carpophillata Staudinger, 1897, Idaea nitidata (Herrich-Schäffer, 1861), Sympistis campicola Lederer, 1853, Sidemia spilogramma (Rambur, 1871), Polia malchani (Draudt, 1934), Sideridis lampra Schawerda, 1913.

New records of Crambidae (Insecta, Lepidoptera) from Omsk Region

Four species of Crambidae are reported from the territory of Omsk Region of Russia. Titanio ledereri (Staudinger, 1870) is new to Asian part of Russia, Loxostege peltalis (Eversmann, 1842), Catoptria verellus (Zincken, 1817) and Ostrinia peregrinalis (Eversmann, 1852) are new to West Siberia.

Populations of Agrostis diluta Kurcz. and Psathyrostachys caespitosa (Sukaczev) Peschkova in Yakutia: dynamics of vitality

In Yakutia, natural floodplain meadows and steppes have long been involved in economic activities. To develop methods of rational use, one needs to constantly consider the state of vegetation, mainly its constituent populations. Our research focuses on studying the dynamics of the vitality of the populations of the Agrostis diluta Kurcz. and steppe Psathyrostachys caespitosa (Sukaczev) Peschkova cereals. These species play an essential role in the composition of vegetation cover. We determined the vitality coefficient IVC. Our study of populations over several years has revealed the dynamic mobility of the vital structure, which is of adaptive significance and ensures the sustainability of populations. We have found that the vital structure of the cereal populations of the meadow Agrostis diluta and the steppe Psathyrostachys caespitosa during long-term studies (2007–2013 and 2007–2016, respectively) is heterogeneous. In unfavorable humidification conditions, we characterize years as depressive. Under favorable conditions of humidification, they quickly turn into thriving plants. In addition to the weather of the vegetation periods, habitat specificity affects the vitality of species populations that differ in ecological and coenotic characteristics. The Q quality index and IVC correspond to each other by year and form a clear descending order during the transition from a thriving to a depressive state. Currently, the vital state of the populations of both species is satisfactory.

Comparative analysis of phytolith spectra of steppe and forest phytocoenoses

The primary research goal is to identify differences and diagnostic features of the phytolith spectra of the steppe and forest phytocoenoses. The paper presents the research results of recent soils from various communities. The authors employ the phytolith analysis method. The isolation of phytoliths from recent soils has been carried out with the help of the maceration method and from plants – the dry ashing method. The authors counted the phytoliths using the Olympus BX-51 light microscope. Additionally, the authors have compiled the spectra using the 2C software. The paper compares the phytolith spectra of plain and mountain steppe phytocoenoses. The comparison reveals that the considered plain communities are more similar in phytolith composition than the mountain ones. The following morphotypes are common for all spectra: low conical rondel particles and psilate ribbed particles. These are the forms that characterize steppe communities. Analysis of phytolith spectra of the mountain forest communities demonstrates that the presence of ribbed particles of psilate is common for all spectra. The common feature of all forest spectra is the presence of psilate symmetrical particles, polylobate trapeziforms, lanceolates (trichomes) with a massive base, and trapeziform bilobate (“Stipa-type”) particles. In the spectra of all pine forests, there is a low content or complete absence of needle phytoliths. Diagnostic features of individual phytocoenoses have not been found. The most significant is the ratio of individual phytolith forms in the phytolith spectrum. The comparative analysis of phytolith spectra of the phytocoenoses in the south of western Siberia is carried out for the first time.

Microlepidoptera of Omsk Region (Russia). Communication 2. Families: Eriocraniidae, Nepticulidae, Opostegidae, Adelidae, Prodoxidae, Incurvariidae, Psychidae, Tineidae, Roeslerstammiidae, Bucculatricidae, Yponomeutidae, Argyresthiidae, Plutellidae, Acrolepiidae, Glyphipterigidae, Ypsolophidae, Lyonetiidae, Bedelliidae, Elachistidae, Parametriotidae, Scythrididae, Momphidae, Blastobasidae, Batrachedridae, Cosmopterigidae, Epermeniidae, Choreutidae

The second сommunication on the Microlepidoptera fauna of Omsk Region of Russia includes information about 115 species. Most part of them is new to the regional fauna. The list includes 14 species recorded from the Asian part of Russia for the first time, among them Opostega salaciella (Treitschke, 1833), Myrmecozela ochraceella (Tengström, 1848), Bucculatrix ulmella Zeller, 1848, Euhyponomeutoides ribesiellus (Joannis, 1900), Glyphipterix equitella (Scopoli, 1763), Mendesia farinella (Thunberg, 1794), Elachista humilis Zeller, 1850, Elachista littoricola Le Marchand, 1938, Elachista pollutella Duponchel, 1843, Elachista pullicomella Zeller, 1839, Biselachista albidella (Nylander, 1848), Scythris flavilaterella (Fuchs, 1886), Pyroderces argyrogrammos (Zeller, 1847), Epermenia iniquella (Wocke, 1867).

Syntaxonomic and ecological peculiarities of extra-zonal pine forests with participation of Acer negundo L. from the forest-steppe and steppe zones of Altai Krai (South-Eastern Siberia)

The syntaxonomic analysis of pine forests with Acer negundo occurring on fluvio-glacial sandy deposits of Altai Krai (South-East Siberia) was made based on 93 releves. It was established that Acer negundo takes a different phytocenotic part in 2 associations, 2 variants, and 6 no-ranked communities of 4 classes and 4 orders according to the Braun-Blanquet approach. The method of detrended correspondence analysis (DCA coordination) implemented in the DECORANA software package was used to confirm the ecological and floristic integrity of the identified vegetation units. New data on the spatial syntaxa distributions depend on the complex humidity gradient, soil fertility, and anthropogenic factors. Acer negundo is most abundant and common in the communities of the Brachypodio-Betuletea pendulae class, which are characterized by habitats with moderate moistening and greater soil fertility. In the spatial series considered, according to the soil fertility and humidity gradients, we observe an increase in Acer negundo in the Vicia sylvatica – Pinus sylvestris community and an increase in the activity of mesophytes and mesohygrophytes that are more demanding to soil fertility.