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The annual cycles of the Northwestern Siberian warblers are analyzed in order to identify the features that determine the possibilities of further development of the Subarctic in the conditions of current climate change. The penetration of Philloscopus inornatus, Ph. trochiloides and Silvia curruca into the Subarctic is limited by woody vegetation, Ph. borealis - by high willows of the river valleys of the Middle Yamal. Ph. trochilus, Ph. collybita and Acrocephalus schoenobaenus inhabit the strip of subarctic tundra of Yamal. The last three species are moving in a northerly direction. The probable advance of forest-tundra-tundra landscapes to the north under conditions of further warming will entail the northward movement of forest and shrub birds, not only warblers, since there are no factors preventing this.

In this work reconstruction of past vegetation and fire dynamics in north Altai was performed by pollen and charcoal investigation of peat deposits of Maly Labysh Mire located in the upper reaches of the Kondoma River in Gornaya Shoriya National Park (52.6306° N, 88.0829°^{E, 490 м a. s. l.). Lithology and radiocarbon dating has shown that the swamp is of lacustrine origin. The lake originated about 3000 years ago, and about 2200 years ago it turned into a swamp. Spore-pollen analysis of lacustrine and peat deposits revealed repeated changes in the vegetation cover, probably caused by climate instability during the last 3000 years. In general, 2 humid millennial periods (3000-1800 cal. yr. BP and 550-200 cal. yr. BP) were identified when the role of fir ( Abies sibirica ) increased in the forests, alternating with 2 drier periods (1600-900 cal. yr. BP and 200 cal. yr. BP - contemporary) when the fir gave way to birch ( Betula pendula and Betula alba ) forests. The article represents also data on the dynamics of paleo fires in the area of the Maly Labysh Mire based on micro- and macrocharcoal analyzes. It was found, that in peat deposits of Maly Labysh Mire the maxima of micro-charcoals record wetter periods, but macro-charcoals - drier periods, while periodical flooding of the bog with river waters took place. With transition of mire from the flooding regime to unflooding regime, the microcoals and macrocoals began to synchronously reflect drier periods. The results of the study showed that the frequency and intensity of fires in Gornaya Shoriya in the last two thousand years correlate well with previously identified periods of lowering of the groundwater level in the mire [Kuryina, Blyakharchuk, 2020] and with a decrease in the amount of atmospheric precipitation in the Holocene [Arkhipov, Volkova, 1994]. A conclusion is drawn about connection of paleo fires with dynamics of humidity of climate, which in complex influenced on vegetation change in Gornaya Shoriya.}

In this work, a dendroecological study of the parameters of annual rings of Scots pine ( Pinus sylvestris L.) trees in the forest-steppe and steppe zones of Eastern Transbaikalia was carried out. For the first time, two new tree-ring chronologies (Nov and Tz) were built for the study area. They were constructed using digital growth ring anatomy methods and include four parameters: tree ring width, early wood width, late wood width, and late wood optical density. The analysis of the obtained chronologies made it possible to estimate the parameters of tree growth in the conditions of the forest-steppe (Nov) and steppe (Tz) zones and to reveal the presence of a reliable connection between them. Calculation of sliding correlation coefficients revealed periods of falling correlation coefficients below reliable values. This indicates the impossibility of constructing a generalized regional chronology for the forest-steppe and steppe zones of Eastern Transbaikalia. Comparison of the obtained chronologies with meteorological parameters (surface air temperature and atmospheric precipitation), with the calculated indices of aridity and moisture (Selyaninov’s hydrothermal coefficient, Pedya’s aridity index, Palmer drought severity index) showed the most sensitive characteristics of the annual ring in the study area. In the forest-steppe zone, the highest values of the correlation coefficients were obtained between the average annual precipitation and the annual ring width ( r = 0.59), early wood width ( r = 0.59), and also between the average air temperature for a hydrological year and the late wood width ( r = 0.51). For trees of the steppe zone, the largest significant correlation coefficients were obtained between water year precipitation and the annual ring width ( r = 0.43), early wood width ( r = 0.43), as well as between the Palmer drought severity index for June-September and the width of early wood ( r = 0.52).

The properties of a sandy Ferric Podzol over fluvioglacial deposits and the root mass of its 0-20 cm layer with Pinus sylvestris L. fine roots (≤ 3 mm in diameter) were studied in a mid-taiga cowberry-type pine stand. Keeping in mind the structure of the phytogenic field of a tree, the study was subdivided into the “trunk”, “crown”, and “gap” zones. The root mass of the forest floor and the mineral horizons was found to change in different directions in the said zones. In the forest floor, the “trunk” zone was more saturated with roots than the “gap” zone, while the trend in the soil mineral layer was the opposite. The highest root biomass was associated with sites that were the richest in soil nutrients and organic matter (NPKC). The cellulolytic activity and eco-physiological parameters of the microbiota varied in the studied horizons. Cellulolytic activity in the forest floor was the highest near tree trunks, while the spatial variation of this parameter in the mineral body of the soil was less pronounced. A correlation was detected between the contribution of root respiration to total СО₂ emissions from the soil surface and the biomass of fine roots (≤3 mm) in the 0-20-cm soil layer. The effect of the soil thermal regime on root mass in different zones of the phytogenic field was studied. Soil temperature variation due to the redistribution of solar energy by the canopy results in a higher root mass in areas receiving more heat. The zone with better heated soils is the canopy gaps. The effect of the temperature of the soil’s root mass is more explicit in the mineral layer. The results of this study can be used in environmental monitoring and in predictive assessments of the effects of climate change on boreal forest ecosystems.

The abundance, biomass, and size-morphological structure of heterotrophic bacterioplankton were determined in freshwater environments of the Svalbard archipelago (Norway), differing in morphometry and trophic level. The quantitative parameters of bacterioplankton varied within wide limits and increased along the trophic gradient of the waters. Medium-sized cocci and coccobacilli reached up to one third of the total abundance and a half of the total biomass of bacterioplankton. The abundance and biomass of small cocci varied over a wide range, while small rods were, on the contrary, relatively stable in these parameters. With an increase in trophic status, the proportion of small cocci in the community increased, while the proportion of rods and vibrios decreased. The proportion of medium-sized cocci and coccobacilli changed less, although there was a tendency for its increase in the trophic gradient.

Aquatic vascular plants at different stages of their life cycle exhibit different physiological and metabolic activity, resulting in changing habitat conditions for hydrobionts. The hydrochemical parameters of the environment, the concentrations of phytoplankton pigments, the abundance of bacteria and zooplankton were studied in experimental ecosystems (microcosms), including actively vegetating and completing the vegetation of aquatic plants. In microcosms with actively vegetating hornwort Ceratophyllum demersum L. the concentration of P_tot, Mg²⁺ and BOD ₅ increased, and Na⁺ and Ca²⁺ decreased. In systems with a dying arrowhead Sagittaria sagittifolia L. the concentration of K⁺ increased to the greatest extent, P_tot, Cl^-, and BOD₅ to a lesser extent, and the concentrations of SO₄^2- and O₂ dissolved in water decreased. In the presence of plants, higher concentrations of phytoplankton pigments were observed in comparison with the control. The quantitative indicators of bacterioplankton did not differ. The number and biomass of zooplankton in general and the dominant species Daphnia longispina in microcosms with plants exceeded these indicators in the control. The hornwort, which lost half of the biomass, but continued vegetation, had a stronger stimulating effect on the abundance of zooplankton than the arrowhead, which finished vegetation.

This review considers the history of the development and implementation of the method of gibbsite thermal activation in Russia, the physicochemical foundations of the method, and the outlooks for its use for the preparation of supports and catalysts based on aluminium oxide. The contribution of R. A. Buyanov and his collaborators to the development of scientific foundations and the practical application of the thermal activation method is considered.

The synthesis of amide complexes of O,O-di(alkyl)aryldithio phosphates of metals (Co, Cu, Zn) with acetamide, benzamide and salicylamide was carried out. It was found that one of the advantages of these amido complexes is the absence of odour amines and the possibility of their use in neutral, acidic and hydrocarbon media. The composition and structure of the obtained amido complexes were confirmed by analytical procedures and IR spectroscopy. The anticorrosion properties of preservation liquids based on the synthesized amido complexes with the spent turbine oil T-30 were studied on steel plates in three media: in a G-4 hydrochamber (temperature 40±2 °C, humidity 95±3 %); in seawater; in the 0.001 % solution of sulphuric acid. Their high efficiency against corrosion was revealed.

Dimethyl-, diethyl[1-allyl(3-α-naphthylprop-2-ynyl)]ammonium and -piperidinium bromides were synthesized by alkylation of dimethyl-, diethyl[1-allyl(3-α-naphthylprop-2-ynyl)]amines and -piperidine, obtained by Stevens rearrangement of dimethyl-, diethylallyl(3-α-naphthylprop-2-ynyl)]ammonium and -piperidinium bromides, with allyl or propargyl bromides. 2,2-Dimethyl-, 1-allyl-3 a ,4-dihydronaphtho[ f ]piperidinium bromides were obtained through base-catalyzed cyclization of dimethylallyl[1-allyl(3-α-naphthylprop-2-ynyl)]ammonium and -piperidinium bromides in the yields of 90 and 88 %, respectively. It is shown that the interaction of propargyl analogs with a catalytic amount of the base leads to the formation of compounds of unknown structure.

Predictive analysis of the state and course of works aimed at the construction of nanosized robots of different types and purposes is presented on the basis of literature and own sources of information. Two principally different methods of their construction are distinguished:
1. Molecular assembly or another manual version. The human factor is decisive here.
2. Alternative method. Nature itself creates the functional structures to govern nanotechnologies. The problem is in finding them and programming.
The first method turned out to be too complicated and attractive only in imagination, as in the saying: the devil is in the details.
The second method turned out to be great luck. On the basis of the available knowledge, the previously unknown natural phenomenon possessing the functional structure was found and decrypted. A physicochemical nanosized robot (PCNR) has been created, and the scientific basis of the technology to manufacture PCNR for different purposes have been established.