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Long-term studies of the dynamics of forest ecosystems in different landscape-geomorphological conditions have shown their spatial heterogeneity, the dominance of forests at different stages of restoration. A close relationship with soil formation in the restoration cycles of the forest ecosystem is noted: soil degradation in the phase of climax coniferous forest and restoration in the phase of derivative deciduous forests. It was found that the duration of the succession is the main factor in the sustainability of forest ecosystems. The recovery time is determined by the conditions of the edaphotop, the biological characteristics of the forest-forming species and varies from 150-600 years, which exceeds the duration of regional (secular and intra-secular) climatic cycles. At the same time, the complex structure of the humus profile of soils indicates a change in landscape conditions associated with global climate changes in millennial cycles. Anthropogenic transformations shift the ecosystem out of balance, which significantly delays its restoration or makes it unattainable.

Various types of biomineral layers have been identified and characterized at the rock art sites of the Minusinsk Basin. On the surface of sandstone, on which images were applied in ancient times, cyanobacterial biofilms, biofouling dominated by lichens, mosses, primary soils develop, and are also formed by mineral crusts, to a greater or lesser extent inhabited by microorganisms. Cyanobacterial biofilms formed by Gloeocapsopsis magma are the dominant form of biolayers on open rock surfaces exposed to intense insolation. The most intense development of microorganisms was noted on light-colored calcite-containing crusts with a porous surface. Gypsum crusts are poor in organic matter content and are practically not colonized by microorganisms. By itself, the growth of gypsum crusts leads to serious damage to the surface layer of the stone and can be one of the main processes leading to the loss of the rock art.

The article deals with the issues of methodological support and methodological support for the analysis of risk-forming situations in environmental management at the regional level. The principles and criteria for assessing natural hazards and risks are presented, taking into account the geosystem situation, natural-climatic and socio-economic conditions of the territory. The article provides information on the development and application of methodological approaches in the comprehensive assessment of the state of the natural environment and the likelihood of environmental and socio-economic risks. On the example of the taiga territories of Western Siberia and Tomsk region, the dynamics of dangerous situations, their classification, spatial differentiation and probability of occurrence are revealed. The features of the sectoral approach (forest management, agriculture) to the assessment of environmental risks associated with changes in the natural and climatic conditions of the territory are determined. The article presents the experience of GIS analysis and zoning, examples of estimated mapping, which take into account the impact of dangerous and unfavorable processes on various branches of environmental management. It is concluded that the degree of natural and climatic risk of the Tomsk region is increased.

Long-term studies of the dynamics of forest ecosystems in different landscape-geomorphological conditions have shown their spatial heterogeneity, the dominance of forests at different stages of restoration. A close relationship with soil formation in the restoration cycles of the forest ecosystem is noted: soil degradation in the phase of climax coniferous forest and restoration in the phase of derivative deciduous forests. It was found that the duration of the succession is the main factor in the sustainability of forest ecosystems. The recovery time is determined by the conditions of the edaphotop, the biological characteristics of the forest-forming species and varies from 150-600 years, which exceeds the duration of regional (secular and intra-secular) climatic cycles. At the same time, the complex structure of the humus profile of soils indicates a change in landscape conditions associated with global climate changes in millennial cycles. Anthropogenic transformations shift the ecosystem out of balance, which significantly delays its restoration or makes it unattainable.

Long-term variations of stable carbon isotope rations in tree ring cellulose for two forest sites of the Ob-Tom interfluve territory are analyzed. At the first site, the expected decrease in δ¹³С values was found, but its rate was higher than the global one by 0.16-0.2 ‰/10 years. At the second site, located 20 m from the peatland, the δ¹³С value was increased until 1978 and then decreased at the same rate as in the first site - 0.2 ‰/10 years. We assume that the δ¹³С values variations in tree ring cellulose at the second site reflect changes in δ¹³С value of СО₂ emitted from the peatland. The reason for the changes in dynamics after 1978 is probably the influence of the Tomsk underground water intake, which led to the drying up of the peatland and, accordingly, a decrease in the δ¹³С value in СО₂.

Results of the studies of powder and structural composites (plates) based on low-density polyethylene (LDPE 15803-020 and LLDPE 6101RQ) and ultra-high molecular weight polyethylene (UHMWPE from Braskem company) and inorganic additives (SiC, TiO₂, CaCO₃, SiO₂) within concentration range 0.05-70 wt. % are presented. It is established that ultradispersed inorganic particles promote a decrease in the amount of the crystalline phase of polymers and an increase in wear resistance for the samples: UHMWPE (containing 7 wt. % SiC ( S _sp = 10 m²/g)) - by a factor of about 150; LDPE 15803-020 (20 wt. % SiC ( S _sp = 6-10 m²/g)) - by a factor of 2-2.5. For LLDPE 6101RQ samples with the low additive content (0.05-5 wt. % ТiО₂, SiO₂, CaCO₃), tensile strength increases by 7-24 %, мodulus of elasticity (along the axis) increases by a factor of 1.2-1.4, and relative elongation at fracture decreases within the range of 13.5-38.0 %. The maximal increase in tensile strength is observed for samples containing 20 wt. % SiO₂ and 50 wt. % ТiО₂ (by 38.5 and 43.6 %, respectively), while relative elongation at fracture decreases 2.8 and 3.9 times, and мodulus of elasticity increases by a factor of 1.9 and 2.0, respectively. Comparative data on the oxygen permeability of the plates, with different methods for the initial components’ mixing, show that samples prepared by mixing the polymer with inorganic additives in a mixer (the amount of additives 5 and 20 wt. %) gave a decrease in oxygen permeability within 5.6-11.2 %, while the samples prepared through mixing in a planetary mill activator, AGO-3, showed a decrease in oxygen permeability in the range of 16.8-28.7 %, compared to the original sample.

The catalytic properties of ZSM-5 type zeolites modified with copper, zirconium and boron in the process of obtaining high-octane gasoline from the straight-run gasoline fraction of gas condensate have been studied in a flow-through installation at atmospheric pressure without hydrogen within the temperature range 350-430 °C. Cracking and aromatization of hydrocarbons mainly take place on non-modified HZSM-5 zeolite; with an increase in reaction temperature from 350 to 430 °C on HZSM-5, an increase in the content of aromatic hydrocarbons (from 10.8 to 16.9 mass %) and a decrease in the yield of liquid hydrocarbons (from 68.6 to 60.8 mass %) is observed. Modification of HZSM-5 zeolite with copper significantly changes the content of high-octane components in the catalyzate. An increase in copper concentration in HZSM-5 up to 2.0 mass % leads to an increase in the ability of the catalyst to provide isomerization and aromatization. At the optimum temperature (380 °C), the content of isoparaffinic and aromatic hydrocarbons in the catalyzate increases up to 36.8 and 24.6 mass %, respectively. An increase in the concentration of copper in HZSM-5 up to 3.0 mass % promotes an increase in the aromatization ability of the catalyst. Modification of the catalyst 2 % Cu/HZSM-5 with boron in the amount of 0.5-1.0 mass % has a small effect on its isomerization and aromatization properties, but significantly increases the yield of liquid products. It is found that the modification of the catalyst 2.0 % Cu-1.0 % B/HZSM-5 with zirconium in the amount of 0.5-1.5 mass % significantly increases the content of isoparaffinic hydrocarbons in the catalyzate (42.1-43.5 mass %). The highest activity is exhibited by the bimetallic catalyst consisting of 1.0 % Zr-2.0 % Cu-1.0 % B/HZSM-5, which allows obtaining the gasoline fraction with 88-94 octane number according to the research method. The addition of boron in the amount of 1.0 mass %, followed by the introduction of zirconium and copper, makes it possible to increase the duration of catalyst operation by up to 200 h. With respect to the content of isoparaffinic and aromatic hydrocarbons and benzene, the gasoline fraction corresponds to the Euro-4 and Euro-5 class. The possibility of refining low-octane straight-run gasoline fractions in the presence of a bimetallic catalyst under unconventional conditions without hydrogen supply to the reaction zone at atmospheric pressure is demonstrated.

As a result of sedimentation, suspended particles carry chemical pollution from the surface layer of water into bottom sediments, playing a significant role in waters’ self-purification from mercury. For the purpose of establishing the features of mercury distribution in the surface water of coastal and open-sea areas and concentrating it in the suspended matter, mercury concentrations were measured in water sampled in different seasons of the years 2018-2019 from the surface water layer of the Black Sea, and empirical dependencies of the parameters of mercury concentrating by the suspended matter on the seasons and depths of the water areas were determined. It is demonstrated that dissolved mercury forms dominated in the Black Sea during the period under investigation, regardless of the seasons. The concentration of dissolved mercury form in the water of the Black Sea varied from 10.0 to 130.0 ng/L, and the average concentration was 54.9 ng/L. The coefficient of mercury accumulation by suspended matter (K_ss) was determined, which varied within the range (0.01-3.33)•10⁶. The values K_ss > 10⁶ provide evidence of the high concentrating capacity of suspended matter in sea water and prevalence of sedimentation over other biogeochemical mechanisms of water self-purification. The formula for calculating the percentage pool of mercury in suspended matter was analysed. The values of the percentage pool of the suspended form of mercury were obtained, ranging from 3.2 to 75 % of the total mercury content in the surface water of the Black Sea for its coastal and open water areas in different seasons of the year.

Mumijo is a product of natural origin, composed of a complex mixture of organic compounds and exhibiting physiological activity in some cases. The Altai mumijo is widely known in Russia, but Tuvinian mumijo has been studied much less. The data on the location of mumijo in the Republic of Tyva, its elemental composition, isotopic composition of carbon, amino acid spectrum, and mineral formations associated with mumijo are presented. The investigated mumijo is a waste product of small rodents, which underwent aqua transfer, weathering and bacterial processing.

The carbon isotope composition analysis of 51 melliferous plants species of the Tomsk region, 35 samples of pollen load, 77 samples of honey and 36 samples of dead bees taken from different geographic regions of Russia was carried out. The stable carbon isotope ratios were measured to reveal the applicability of isotope ratio mass spectrometry to detect honey adulteration with sugar syrup and to determine the geographical origin. Seven adulterated honey samples were identified with the help of the method of honey adulteration detection based on comparison of the ¹³C/¹²C isotope ratio in honey sample and in the protein isolated from honey, which was an internal standard. Some differences in the carbon isotope composition (δ¹³C) are observed for honey samples from the Tomsk Region collected in 2019 and 2020, which points to the necessity of further studies of the influence of climatic conditions and honey harvesting season on the ratio of stable carbon isotopes in honey. Carbon isotope analysis demonstrated differences between honey samples differing from each other in geographical origin. Higher δ¹³C values are typical for honey samples from the European part of Russia and the Black Sea region. The δ¹³C values of honey from Siberian regions with a lower average temperature or higher air humidity are lower. For local areas, the “canopy effect” was revealed, in which the carbon isotope composition of the pollen load for forest ecosystems is depleted in ¹³С isotopes, compared to meadow ecosystems. Trophic enrichment values (Δ¹³С = 1.0±1.2 ‰) in the chain “pollen load - bee” were also determined.