Home – Home – Jornals – Advanced Search

An analysis of the ecological characteristics of cyanobacteria in Svalbard has been carried out. Two groups of habitats have been identified: aquatic and terrestrial. The main factor determining the development of cyanobacteria is considered to be the degree of water saturation. The variability of habitats can be represented as a gradient of moisture from typically aquatic to dry terrestrial habitats. Based on the number of findings and species richness, it can be concluded that the most favorable habitats for cyanobacteria in Svalbard are 1) rocky communities in conditions of sufficient moisture, 2) exposed soil surfaces on which biological soil crusts form, 3) slow, well-warmed streams, and 4) specific over-moistened habitats such as seepages. Using the example of the analysis of the ecological characteristics of species growing in the archipelago, it is shown that the concept of eurybiont properties of cyanobacteria is not tenable. The greatest plasticity is exhibited by Nostoc commune Vauch. ex Born. et Flah., Microcoleus autumnalis (Trev. ex Gom.) Strunecky et al., Calothrix parietina Thur. ex Born. et Flah., Oscillatoria tenuis C. Ag. ex Gom., Pseudanabaena frigida (Fritsch) Anagn. All of cyanobacterial species, including those mentioned above, have obvious ecological preferences. Analysis of the substrate specificity of cyanobacteria demonstrates that the greatest number of species are found in soil, rocky substrates, and moss-like environments.

A comprehensive paleoecological study of permafrost peat deposits from three locations of the middle reaches of the Yuribey River in the subzone of modern subarctic shrub tundra of the Yamal Peninsula has been carried out. Based on the results of palynological and carpological methods and radiocarbon dating data, the changes in regional and local vegetation and climatic conditions of Central Yamal in the Late Glacial and Postglacial periods are reconstructed. It was found that in this area shrubby tundra with Betula nana were widespread in climatic conditions close to modern ones in the Younger Dryas about 12.6-11.7 cal. ka BP. The penetration of tree species (Betula sect. Betula, Picea obovata, Larix sibirica) and their accompanying boreal herbaceous plants began due to improved climatic conditions in the Early Holocene warming about 10.2-9.7 cal. ka BP. The most favorable conditions for the growth of tree-shaped birch, larch and spruce in the territory of Central Yamal existed in the Early and Middle Holocene in the range of 10.2-4.4 cal. ka BP. At that time, sparse woodlands or even closed forests were common, the climate was much warmer than the modern one. Forest vegetation degraded and open landscapes with tundra communities formed at the end of the Middle Holocene (4.5-4.4 cal. ka BP). The climatic conditions have become close to modern ones.

The analysis was performed for input-condition sensitivity of haemodynamics simulation for the zone of abdominal aortic aneurysm. We took three versions of patient-specific configurations of aneurism and computed the haemodynamics with different spatial and velocity profiles at the inlet. Their impact on haemodynamic characteristics was evaluated. At total, the study was performed for three spatial variants (uniform, parabolic and parabolic-and-secondary-flow velocity profiles) and three versions of time behavior of velocity profiles: this produces nine cases for every of three chosen geometries. The study demonstrated that we can neglect the impact of spatial profile for inlet velocity (including the non-coaxial velocity vector components). Meanwhile, the value of reverse diastolic flow is significant for the solution. However, simulation in the zone of abdominal aortic aneurysm does not demonstrate great differences in simulation results for the values of wall shear stress and velocity for the data averaged over a cardiac cycle. For the distribution of the oscillation index of shear, the maximum deviation from the basic solution is about ~ 10 %, which is quite acceptable for clinical applications.

Although there are no official and permanent criteria for determining the position of your name in the list of authors of an article, the principle of “authors at the both sides of the list” is increasingly used in biomedical publications. The best addition to it is a detailed indication of the contribution of each author to the creation of the article.

In the indigenous southern taiga fern-forb fir forests on the Tom-Yaya interfluve (Tomsk Oblast), the characteristics of tree stands, underbrush, undergrowth, coarse woody debris, ground cover, soils and their contribution to carbon sequestration were studied. The average stock of the forest stand for the type of biogeocenosis was 315.8 ± 56.1 m³/ha, the average stock of the Siberian fir ( Abies sibirica Ledeb.) in different stands varied from 99.2 to 201.4 m³/ha. In terms of forest health condition, the forest stands are weakened to varying degrees, the fir elements of the forest stands are stronger, which is largely due to their damage by the invasive four-eyed fir bark beetle ( Polygraphus proximus Blandford). The underbrush is sparse or of medium density (880-2720 pieces/ha), formed mainly by red raspberry ( Rubus idaeus L.) and rowan ( Sorbus sibirica Hedl.). Undergrowth with an absolute predominance of fir, its number (800-920 trees/ha) characterizes unsatisfactory regeneration in all studied stands. The average volume of deadfall for the type of biogeocenosis was 2.1 ± 0.5 m³/ha, stumps 3.3 ± 0.8 m³/ha, brushwood - 9.2 ± 5.3 m³/ha. The features of the phytocenosis include high values of floristic diversity (131 species), species richness of the grass cover (105 species) and species richness of plant communities (57 species per 400 m²). The increased participation of ferns in the composition of the grass stand is due to the presence of windows occupying from 5 to 30 % of the area of the phytocenosis, formed in stands at the site of fallouts and dead trees, mainly due to the drying out of fir damaged by the four-eyed fir bark beetle.. For the first time, data have been obtained on the phytomass of the ground cover of southern taiga fir forests in Western Siberia, estimated on average at 0.88 t/ha, with a wide variation of this indicator due to the peculiarities of the horizontal structure of the ground cover and different illumination in sub-canopy parcels and windows. The features of the composition, structure and thermal regime of the soils of the studied biogeocenoses are shown. Data are presented on changes in the productivity of phytocenoses, soil humus and carbon reserves in various components of the studied forests.

The Tellerman experimental forestry of the Institute of Forest Science, Russian Academy of Sciences, located in the southeast of Voronezh Oblast, has a long history. It was established on the initiative of Academician V. N. Sukachev in 1944 as a place to conduct complex long-term studies in broad-leaved forests on the border between forest-steppe and steppe. For almost 80 years specialists of different profiles worked in the territory of the forest area: foresters, geobotanists, soil scientists, zoologists, microbiologists, entomologists, phytopathologists. Extensive studies was carried out on the hydrology of the massif and water regime of stands, the environment-forming role of the forest, phytomass reserves were determined, productivity of stands in different forest types was determined, and a cycle of silvicultural experiments was established. The comprehensive study of biogeocenoses also included root systems, phenological, geobotanical, zoological, entomological, microbiological and mycological studies. The scientific basis for the establishment of pedunculate oak ( Quercus robur L.) crops in the forest-steppe was developed, taking into account its form diversity and the results of silvicultural experiments laid down in the first decades of the forest region’s existence. The study of silvicultural aspects of oak stands degradation allowed us to develop practical methods of reproduction of oak forests on clear cuts of stands mixed with oak by sowing acorns with a shortened period of thinning.

The phenology, productivity, intensity of gas exchange and resistance to biotic factors in climatic ecotypes of Siberian stone pine ( Рinus sibirica Du Tour) from latitudinal (from the West Siberian forest tundra to the low mountains of the Western Sayan) and longitude (from the Urals to the Northern Baikal region) profiles were studied in the 30-year clone archive at the scientific field station «Kedr» of the Institute for Monitoring of Climatic and Ecological Systems, Siberian Branch of the Russian Academy of Sciences. It has been established that Siberian stone pine is characterized by a high level of hereditarily determined ecological and geographical differentiation in productivity and resistance to biotic factors (pests and fungi diseases) when growing vegetative progeny in the south of the forest zone. The main factor of differences between ecotypes is the heat supply of the growing season in their places of origin. It increases significantly more from north to south than from east to west. Therefore, the differences between latitudinal ecotypes are much greater than between longitudinal ecotypes. The intensity of respiration depends more than the intensity of photosynthesis on the climate in which a given population was formed. Ecotypes from cold habitats have significantly higher respiration costs. This is an important factor in reducing their productivity in warmer climates. Being weakened by the imbalance between photosynthesis and respiration, they are damaged by pests and diseases which becomes an important factor in further reducing productivity. In conditions of global warming, ecotypes from warmer climates are not inferior to the local ecotype in terms of resistance to biotic factors and surpass it in productivity. Therefore, they are recommended to be actively used for breeding.

The interaction of the main forest-forming species of Siberia: Siberian spruce ( Picea obovata Ledeb.), bush birch ( Betula fruticosa Pall.), Scots pine ( Pinus sylvestris L.), aspen ( Populus tremula L.), Siberian larch ( Larix sibirica Ledeb.), and Siberian stone pine ( Pinus sibirica Du Tour) with agro-gray soil is considered. The study is carried out in a special long-term experiment with forest crops, initiated by prof. N. V. Orlovskiy in 1968-69 in the southern taiga on the territory of the Kemchug Upland. It was revealed that biological characteristics and successional position of tree species significantly influence all components of the phytocenosis. The biggest changes were recorded under the canopy of early successional coniferous (larch) and small-leaved (birch and aspen) species, while late successional species - spruce and cedar - at this stage significantly limit the development of subordinate layers. Over the 45-year period of growth of forest crops, the soil profile is formed due to the differentiation of the arable substrate of the soil-forming species into genetic horizons. The influence of the forest canopy on planted agro-gray soil occurs gradually and intensifies with the growth and development of crops, the formation of a litter horizon and covers all soil properties. Active modern soil formation affects the mineral soil layer 0-10 (13) cm. Vertical flows of matter and energy entering the soil in the process of increasing capacity and intensity of the biological cycle are the main factor in the formation of the soil profile. The development of soil under forest crops under the conditions of a long-term zonal experiment was noted.

Two lime tree species: European - small-leaved lime ( Tilia cordata Mill.) and Far Eastern - amur lime ( Tilia amurensis Rupr.) grow in the arboretum of V. N. Sukachev Institute of Forest, Siberian Branch, Russian Academy of Sciences experimental station «Pogorelskiy Bor». Small-leaved lime tree has 9-16 m in height and 10-36.5 cm in diameter, amur lime tree has 11.5-14.5 m and 7.5-21.5 cm, accordingly. Plants of both species are characterized by high winter hardiness, they are not damaged with spring frosts and rarely attacked by pests. The lime trees begin blooming in the middle of July when the sum of effective temperatures reaches about 800 degrees/day (42.2-43.0 % of the total t _ef > 5 for the year). They continue blooming during 10-17 days. A fruits - lime-capsules ripen in September. The small-leaved lime tree capsules were 5.7 mm in length, 4.4 mm in width and 23.6 g in weight per 1000 pieces, its seeds were 4.0 mm, 3.0 mm and 14.5 g, accordingly. Sizes of amur lime tree capsules and seeds were similar - 5.3 mm, 3.9 mm and 23.8 g for the first ones and 3.9 mm 2.6 mm and 16.1 for the second ones. The part of empty seeds in small-leaved lime tree was 70 % but the part of such seeds in amur lime tree was 30 %. At the same time, the good quality of seed samples of both species did not exceed 30 %. On the territory of the arboretum there is natural regeneration of lime tree, including self-seeding. It is the most abundant at a distance of 50-100 m from the mother plants, where its density is 25-41 pieces per square meter.

A review of the contents, processes of writing and reconstitution from manuscript materials of V. P. Grechkin’s monograph «Lesopathological characterization of the forests of the USSR by separate natural and geographical zones» is presented. Edited by Yu. I. Gninenko. In 3 volumes. VNIILM, 2019-2021.