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A study was conducted on the buried soils identified at the base of the foundation of the Cabin of Peter the Great in Saint Petersburg, Russia, to help trace the Late Holocene landscape evolution in the lower reaches of the Neva River. The Cabin is a small wooden house, which was the first residence of Peter the Great in a newly emerged Saint-Petersburg. The house was built of pine logs on the Neva River's right bank. The time of its construction is now regarded as the city's founding date (1703). The pedocomplex with two buried soils has not been truncated and retains a record of the depositional environment, pedogenesis, vegetation history, and human activity before the construction of the city of Saint Petersburg. This pedocomplex was studied using various field and laboratory methods including soil morphology at macro-, meso-, and microlevels, and a full set of microbiomorphic analyses (diatoms, pollen, spores, phytoliths, plant detritus, and amorphous organic matter) supported by radiocarbon dating. The sediment sequence was formed in a contrasting depositional environment. The microbiomorphic studies indicated that the initial substrate was formed in aquatic environments. The analysis of diatoms suggested that these sediments were accumulated as a result of the River Neva breakthrough from Lake Ladoga to the Gulf of Finland ca 3500 yrs BP, which provided additional evidence for the River Neva formation. Soil analyses revealed two inundation events, with the earlier flood related to the termination of the Lake Ladoga transgression (LT) and the breakthrough of the Neva River, whereas the latter flood was likely to be connected with an increase of the fluvial activity. Those two inundation events were followed by two stages of pedogenesis. Both soils indicated the hiatus in sedimentation and were represented by Subquatic Umbric Gleysols that were the most widespread indigenous soils in the XVII century. The pollen data suggest that human impact started at ca 800 yrs BP and eventually resulted in the deforestation and the initial agricultural exploration of the study area. Saint Petersburg is the only large city in Russia that could be at risk from flooding if the sea level rises due to continuing global warming. Our research shows that the city's historical center was twice subjected to flooding in the Late Holocene, even without rises in the sea level. Therefore, the detailed analysis of the environmental dynamics within the Lower Neva area and the assessment of its possible consequences for the city are of great importance.

This research provided a model of genesis of soils in North-West Siberia connecting the stages of their development to the main environmental changes over the Late Pleistocene and the Holocene. The “soil memory” showed that the studied soils had a complex polygenetic origin. A gleyed paleosol with signs of solifluction found at a depth of 2 m was most probably formed during the Marine Isotope Stage (MIS) 3 that is the Karginsky interstadial. The following stage, i.e., MIS2 – the Sartanian cryochron was characterized by the eolian sedimentation of silty material. In the Late Sartanian, new soil formation began in the silty parent material, with a strong platy cryogenic aggregation and grain size sorting. The warmer and more humid climate in the early Holocene induced clay illuviation and allowed for the formation of the argic horizon. Finally, the modern climatic conditions have caused ooidal cryogenic aggregation within upper horizons, however recent frost action has not been as strong as it was during the previous cold stage. Additionally, the modern pedogenesis included spodic and stagnic processes as well as clay mineral transformation. We suppose that such a model of soil evolution could be extrapolated to the northern Cis-Ural region, but not to the west in the Baltic region, where the dynamics of pedogenesis were different.

Changes in the macro-, meso-, and micromorphological properties of plowed migration-mycelial chernozems (Haplic Chernozems) after their conversion into permanent unmanaged fallow state are discussed. The research objects are located in Kursk oblast. The results of the study indicate that changes in the soil morphology are most pronounced in the plow and carbonate-accumulative horizons. As a result of self-restoration processes, the structure of plow horizons improves, and their color becomes darker. Cracks formed as a result of seasonal soil drying disappear, and the structural degradation of plowed soils is stopped. Hard carbonate nodules formed in deep horizons of plowed soils due to seepage and stagnation of moisture in cracks in the periods of bare land disappear over 25–50 years of fallowing. Transitional forms—relatively soft calcareous nodules (beloglazka, white eyes) with a hard core—may be formed. Upon the uptake of soil solutions by roots, the accumulation of carbonates in the form of fibrous calcite takes place in the humus-containing material around the roots. Carbonate incrustations consisting of fibrous calcite are seen along cracks in plowed soils and in young fallows and are thin and fragmentary in the soils of old fallows and in virgin chernozem. The results of the studies of chronosequences of fallowed soils in Belgorod, Rostov, Lipetsk, and Kursk oblasts are generalized. The main features of transformation of the carbonate status of fallow soils are specified: (a) disappearance of hard carbonate pedofeatures in the lower soil horizons, (b) lowering of the lines of effervescence, and (c) a general decrease in the content and total pool of carbonate carbon. The change in the humus state of fallowed soils after the end of plowing are differently directed: the content of stock of humus decrease in gray soils (Phaeozems) and increase in chernozems and dark gray soils.

Srednaya Akhtuba outcrop provides a detailed record of the Late Pleistocene continental and marine deposits and paleosols from MIS5 to MIS1. The MIS5 chronozone is presented by a continuous pedosedimentary sequence with three well-developed paleosols. The paper is based on the study of depositional environment and pedostratigraphy, with OSL chronological framework and precise altitude references. Field data are supported by chemical analyses, micromorphology, and clay mineralogy. A detailed study of MIS5 paleosols was first conducted for the Lower Volga area. Pedosedimentary sequence at that time developed on the river terrace in a backswamp and/or wetland influenced by extremely slow-moving stream after long seasonal floods. Thin loess layers were deposited during the brief episodes of low flood activity, while fluvial heavy loams – at the time of more intensive flooding. Mollic Gleysols and Fluvic Chernozems have been formed in the arid or semi-arid climate with seasonal freezing under productive wet meadows. Changes in the depositional environment resulted in the formation of welded paleosols, marked by textural difference, cryogenic levels, and accretionary humus horizons. Despite the complicated depositional pattern and the influence of seasonal floods, the MIS5 pedosedimentary sequence may serve as a good stratigraphic marker for the onset of Late Pleistocene allowing correlation with loess-paleosol sequences of the whole Ponto-Caspian region and linking it with the global stratigraphic schemes.

During the second half of the Holocene, the Russian Plain experienced several climatic oscillations giving rise to changing vegetation patterns. The spatial variability of vegetation changes and its effects on soils is still a matter of debate. In the present study landscape response to Holocene climatic cycles was analysed on the base of detailed morphological, chemical and microbiomorphic analyses of a paleosol buried under the kurgan of the Abashevo culture (Middle Bronze Age) and a surface soil. Both soils located at the Tokhmeyevo kurgan cemetery (the Middle Volga region, Chuvash Republic, Russia) developed from the same parent material (mantle loam), at the same elevation and in close proximity to each other. Both soils, classified as Retisols, show a similar morphology and key analytical features indicating similar environment. The pollen and phytolith spectra confirm that both buried and surface soils formed under similar forest vegetation. The buried and surface soils at the Tokhmeyevo cemetery could be compared with the previously studied soils of the Sareevo settlement of the Early Iron Age and the Taushkasy kurgan cemetery of the Bronze Age. These studies confirm the stability of the forest environment at the southern boundary of the forest belt since the Bronze Age. At the same time, the buried soil at the Tokhmeyevo cemetery has a thick mollic horizon and black organic coatings overlaying brown clay cutans in the argic horizons, which sets it apart from the surface soil. The radiocarbon dates for the humus in the mollic horizon and black coatings in the argic horizon are surprisingly close to each other (about 5.5 cal ka BP and 5.2 cal ka BP, respectively). The data indicate that the black cutans are derived from degradation of the mollic horizon caused by a sudden increase in humidity during the episodes of extreme summer rainfall events. Our study also prove that the Abashevo people had complicated burial funeral rites. The earth mounds are made of the upper horizons of soils cut off from the surface in the vicinity. The central part of the mound consists of soil bricks with albic material used for the interior, while artificially rumpled material of the argic horizon was used for coverage. The use of albic and artificially rumpled material of argic horizon for earth mound construction implies the similarity between the buried and surface soils since the Bronze Age until today. Thus, the study of such construction techniques is important both for archaeology and paleogeography (paleopedology).

The postagrogenic dynamics of organic carbon (Corg), total nitrogen (Ntot), and density fractions of organic matter (OM) in the dark gray soil (Haplic Phaeozem, Belgorod oblast, Les na Vorskle (Forest on Vorskla) Reserve) and migrational–mycellary Chernozem (Haplic Chernozem, Kursk oblast, Streletskaya Steppe Reserve) were examined. The most significant postagrogenic changes in all the studied soil properties were observed in the top 0–5 cm layer. The contents of Corg and Ntot in this layer of the Phaeozem chronosequence increased by 1.2–1.3 times over 45 years after cessation of farming. The contents of Corg and Ntot in the top 0–5 cm layer of Chernozem chronosequence increased by 1.9–2.0 times over 60 years of the postagrogenic development. The accumulation of Corg took place in all density fractions. In both chronosequences, the free fraction of organic matter (density

Rock freezing affects the soil complexes under maximal temperature gradients and forms a set of specific cryotrasological features in the solid soil matrix. When preserved these features serve as direct or indirect indicators of the past cryogenic conditions. Transformation of soil material on macro- and microscale belongs to the direct indicators whereas gleying in the well-drained positions, conditioned by the permafrost waterlogging is an indirect indicator. A variety of these features observed in the paleosols to the north of the European and West Siberian Loess belt was used by the authors to reconstruct the cryogenic environments of the late Pleistocene.

Rock freezing affects soil complexes with maximum temperature gradients and forms a set of the specific cryotrasologic features in a solid matrix of soils. Remaining unchanged, these features serve as direct and indirect indicators of the past cryogenic settings. Transformation of the soil mass at the macro- and micromorphological levels is related to the direct indicators. Soil gleyzation in the drained positions is conditioned by the occurrence of frozen aquicludes in past settings; it is related to indirect indicators. We revealed the complex of such features in paleosols to the north of the European and Western Siberian Loess Belt and used them to estimate the cryogenic settings of the Late Pleistocene.

Landscape response to Late Holocene climatic cycles is based on detailed hierarchical morphological, analytical and micro-biomorphic research of a soil chronosequence which included a soil buried under a fortification earth wall of the Early Iron Age (Luvic Chernozem) and a surface soil (Chernic Greyzemic Luvic Phaeozem) in the southern forest-steppe area of the East European Plain. Both soils formed on similar surfaces with the same lithology (non-carbonate loess underlain by carbonate loess), at the same elevation, and in close proximity to each other. The buried soil was truncated by at 40 cm and transformed by diagenesis. Taking this into account it was possible to reconstruct the soil formed by the time of burial under the earth wall and to classify it as (Chernic) Luvic Phaeozem. Both surface and buried soils are polygenetic combining the features of humid (forest?) and steppe pedogenesis. The radiocarbon data obtained from the Humic horizon of the buried soil (6750 ± 120 years CalBP) allows bracketing the steppe environment to the mid-Holocene (Atlantic period). Pedogenetic evolution since the Early Iron Age included the next stage of clay illuviation (formation of thin hypo-coatings.) and the development of Greyzemic features. The studied Phaeozems indicate relative landscape stability at the southern boundary of the forest-steppe zone.

Recent revision of the eastern boundary of the last glaciation of Eurasia opened new perspectives in the search of the paleopedological records in the north of Eastern Europe and Western Siberia. We studied paleosol-sedimentary sequences in the Upper Volga and Middle Ob basins as a regional paleoecological record for the Late Pleistocene thermochrons. Two key sections Cheremoshnik and Belaya Gora containing MIS3 and MIS5 paleosol units and additional section Koskovo 2 with polycyclic MIS3 paleosol were investigated. Their timescale are based on C14 and U/Th datings as well as on stratigraphic and paleobotanical correlations. Macro-, meso- and micromorphological observations together with fossil insects and plant macrofossil were used as paleoenvironment proxy. MIS3 paleosols show abundant redoximorphic and cryogenic features that allow interpreting them as gleyic Cryosols. Sub-fossil insects and plant macrofossil reflect the cold climate conditions. Three incipient Ah horizons in Koskovo 2 pedocomplex point to multiple phases of pedogenesis, correlative to the MIS3 paleosol levels in different sections of the Eurasian loess belt and to the major interstadials of the Middle Pleniglacial of the NW Europe MIS5 paleosols are also characterized by gleyzation and peat accumulation, in this case we suppose geomorphological control on hydromorphic pedogenesis; however paleosol in Belaya Gora has clear signs of polygenesis including the phase of clay illuviation. Insect and plant remains from the lower paleosol level of the Belaya Gora section show the transition from cold (terminal phase of MIS6) to warm first, and then to a moderately cold climate (within MIS5). The obtained results contribute to understanding of soil and landscape zonality in the largest plains of Eurasia mostly during the warm phases of Late Pleistocene.

The basal tills of the Late Moscow (MIS 6) Cryochrone form an important component of landscapes in northern Europe, including the center of the Russian Plain. The till is often covered only with a thin cover layer (30–50 cm as an average) – veneers of sands, sandy loams or silty loams, so that surface soils (Retisols) are formed in the bipartite sediments. The study of such soils allows identifying a set of pre-depositional, syn-depositional and post-depositional (pedogenic and cryogenic) features. An assemblage of (macro, meso and micro) morphological features together with analytical data confirmed that soils had been formed within several climatic cycles starting from the Late Moscow time till now, including the last Thermochrone, when the well-developed Argic horizon had been formed. Modern pedogenesis forms embedded profiles within the cover layer depending on the bioclimatic parameters (with Humic, Protospodic or Cambic horizons). The clear record of the final stages of sedimentation and ancient pedogenesis within profiles of soils in bipartite sediments may help to derive paleoclimatic interpretations from the last interglacial - glacial cycle till present. Correlation of these records with other archives in glacial and periglacial areas opens attractive research perspectives.

Landscape response to the Late Holocene climatic cycles was studied on the base of detailed morphological, analytical and micro-biomorphic research of a soil buried under fortification earth wall of the Early Iron Age (around 2000 yr. B.P) and a surface soil. Both soils formed on similar surfaces with the same lithology (mantle loam underlain by calcareous loess), at the same elevation, and in close proximity to each other. The buried soil has a complete profile that was influenced by human activity prior to the burial and subjected to diagenesis after the burial. In addition, both soils (Retisols) show similar morphology and key analytical features indicating close similarity of the landscapes in the study area that existed in the Early Iron Age and those that are present nowadays. Micro-biomorphic assemblages (phytoliths, pollen, microbial genes) support this conclusion. Landscape stability at the southern fringe of the forest zone makes it possible to establish the northern limit of the wide belt, which stretches out from dry steppe to northern forest-steppe, where landscape shifts influenced by the Late Holocene climatic cycles occurred. The features of the diagnostic horizons of the studied Retisols are indicators of stability in the studied time/space range. The study of microbial genes, which was performed in the studied soils for the first time, showed that both content and taxonomic structure of soil microbial communities, are promising paleoclimatic proxies as well as a record of diagenetic changes in buried soils.

This chronosequential study focuses on the vegetation succession, Luvisol pedogenesis, and long-term carbon dynamics during post-agricultural restoration in the temperate broad-leaved forest of European Russia. The study comprises three chronosequences of 37 years (North), 120 years (Middle), and 42 years (South) to cover climatic differences within the study area. The sites of each catena were mostly comparable in terms of climate, soil texture, and land history, but the duration of agricultural abandonment differed between sites. Plant succession developed via a birch forest or a pear-ash woodland to a birch-oak forest with Aegopodium podagraria after 120 years, which indicates the plant association is near to a climax oak forest. Former homogenous plow horizons formed a new morphological stratification similar to natural Luvisols, due to the formation of a well rooted Ah horizon and an O horizon of mull; a change in soil structure from coarse blocky to granular; and decreasing bulk densities. However, plow features were identified even after 120 years of Luvisols restoration. During restoration, the former plow horizons showed minor changes of pH 5.4–5.6 (CaCl2). However, a slightly increased pH value within the newly developed Ah and O horizons induced a new pH stratification of the former plow horizon, approaching the natural soils. Compared to the former plow horizons below, soil organic carbon (SOC) and plant available nutrients (P, K) enrichment was observed within the newly developed Ah horizons. The SOC stocks of the 5 cm mineral topsoil increased from 0.8 to 1.7 kg m−2 (North), from 1.3 to 1.7 kg m−2 (Middle), and from 1.4 to 2.3 kg m−2 (South) during restoration. The surface organic layers showed SOC stocks of 0.1–0.2 kg m−2. However, the levels of the near-natural soils were not reached after 37 years (North) and 42 years (South) of restoration. The model predicted a recovery time of about 150 years to achieve a comparatively steady state. A negative effect of mowing was observed for the modelled SOC accumulation. Despite all these alterations, the study showed no full restoration for many parameters within the chronosequential timescale of 120 years.

The microbiomes of the soils buried under earthwork structures of different age (burial mounds and defensive earth walls) and of surface soils were investigated. Microbial DNA was analyzed by quantitative PCR and sequencing of the 16S rRNA gene amplicons. Both microbial abundance and diversity in buried soils were found to be lower. The taxonomic structure of the buried soil microbiomes differed significantly from that of surface soils: the share of the bacterial phylum Verrucomicrobia was very low. The thickness of the earthwork structure should be sufficient to isolate soil from the effect of plant roots; otherwise, the microbiome may exhibit virtually no difference from that of surface soils. The degree of mineralization of stored organic matter (in the absence of inflow of fresh organic compounds) is probably the main factor affecting the structure of microbial communities in buried soils. The study did not reveal any properties of the microbiomes usable as markers of the type of buried soils.

In the forest-steppe and steppe zones of Russia, soils are subject to prolonged agricultural impact which affected their properties and processes. Therefore, the study of soil transformation under different land-use regimes is an urgent task. The aim of the study is to examine the general patterns of changes in the carbonate state and other properties of soils of the steppe and forest-steppe in Russia of land-use changes from arable to abandoned land (fallow).The objects of research are сhronosequences of fallow Chernozems and Phaeozems. The first сhronosequence is located in the Belgorod region, Russian Federation. It consists of a virgin, arable Phaeozems, and Phaeozems being in the fallow for 40-45 years. The second сhronosequence is located in the Rostov region. It consists of arable Chernozem and abandoned during 14, 20, 30, and 86 years Chernozems. The third сhronosequence is located in the Lipetsk region. It consists of arable Chernozems and abandoned during 15, 25 years Chernozems. The fourth сhronosequence is located in the Kursk region. It consists of a virgin, arable Chernozems and abandoned during 10, 25, and 50 years Chernozems.It is noted that all soils in the abandoned land tend to restore virgin properties. Restoration of vegetation and water regime plays the main role in the acquisition of natural soil properties. For 25-30 years, the structural state is restored in Chernozems and Phaeozems. Overconsolidation of the subsurface horizon disappears in Chernozems in 10-15 years, and in Phaeozems it persists up to 40 years. The restoration of the organic carbon in Chernozems and Phaeozems proceeds in different ways. If in Сhernozems, in general, there is an increase in the content and reserves of organic carbon, then in Phaeozems, in the opposite, their decrease is observed. In the transition from arable to fallow soils, there is a decrease in the content and reserves of carbonate carbon due to a change in the water regime: the intensity of the ascending water flows decreases and descending - increases.In fallow soils, the radiocarbon age of pedogenic carbonates decreases. In arable land "ancient" carbonates are pulled up closer to the day surface. And when plowing stops, they are gradually washed out into the depth of a profile. The greatest 14C age of carbonates is observed in fallow soils with large herbaceous vegetation, which sucks the moisture out from the depth with powerful roots.The recovery time of the natural soil properties depends on the initial state of the soil, the intensity of the agrogenic impact, the use of soil-saving technologies under plowing, and fertilizers use. In general, Chernozems restore faster than Phaeozems. The carbonate state in all сhronosequences acquires the virgin (before plowing) features after about 30 years.

The model of a modern University is characterized by the formalization of its activities within the framework of implementing specific educational programs through the educational process and focusing on the final result in the form of a competitive specialist. As a result, the universal values, the spirit of participation in the acquisition of new knowledge, which were present in previous generations of universities, are leveled. However, the students’ needs in their personal development remain at the present time. This leads to the search for new forms and the use of new technologies to meet this need. Based on the research, the authors propose a Lectures model as one of these forms, which includes scientific and methodological, practice-oriented and personal-development components. This is where the spirit of the University as an element of Higher education, the tasks of the University as an educational organization to train competitive specialists and the needs of the individual in self-development can be realized. Considering the development of information and educational technologies, it is necessary to apply them actively in the already available instruments of the Higher School. The educational process should become interesting, interactive, covering various aspects of the studied disciplines as much as possible. But at the same time, the educational process should not lose its main purpose - the formation of new knowledge and the upbringing of a socially active and positive personality. Taking into account the development of science and technology it is these two components that the Lectures are directed towards.

The article considers the change in the properties of Haplic Chernozems (Aric) on loesslike loams and Сalcaric Phaeozems (Aric) on Paleogene, Neogene red-colored sands with limestone eluvium of the Lipetsk region when they are transferred from cropland to fallow. The main attention is focused on the change in the carbonate status of soils. According to the results of the study, it was found that the transformation of both types of soils formed on different rocks obeys a single trend. Carbonates in Chernozems during their stay in fallow are washed down the profile; stable forms of carbonate pedofeatures gradually disappear. The content and stocks of carbonate carbon in the 0-200 cm layer in Haplic Chernozems (Aric) decrease by 27.5 t/ha by 25 years of fallow state. In Сalcaric Phaeozems (Aric), changes in the carbonate status are less pronounced; nevertheless, it was found that in the arable soil on the fragments of limestone, secondary carbonate films in the form of acicular calcite are formed on top of clay films, which was not observed in the abandoned soils. When the soil is in the fallow, the physical and mechanical properties of the soil improve: the structure of the arable horizons is improved, density decreases. The organic carbon content is reduced. This is an atypical result of postagrogenic transformation of Haplic Chernozems (Aric). In the fallow soils of other regions of steppe and forest-steppe, we observed the process of accumulation of organic carbon. The decrease in soil organic carbon while in the fallow is associated with the use of soil-saving technologies for agricultural use. The radiocarbon age of humus in subsurface horizons increases when soil is in the fallow. The radiocarbon age of carbonates in soils varies depending on the amount of lithogenic calcite inclusion.

The purpose of this work was to characterize the postagrogenic transformation of soil organic matter (SOM). For decision of this purpose the results of chemodestructive fractionation (CDF), the content of chlorophylls a and b , pheophetins and carotenoids, and Margalef's pigment index (PI) were used newly. Subjects of inquiry-humus horizons of soils of arable lands and fallow areas of Poshekhonsky district of the Yaroslavl region of the Russian Federation-were stitch together into two groups with differ in the type of land use. In one of them, the soils remained arable for 30-40 years (arable-arable group), in the other - the soils of arable land for the same time period were transferred to the fallow (arable-fallow group). It was found that increasing the soil water content of fallow plots compared to arable soils can lead: to improved livelihoods of the soil algocenoses (the value of PI Margalef decreased) to increase the carbon content of organic compounds, to increase the number legkomyslenno fraction in the organic component of soil, increased hydrolytic processes that reduce the content of carotenoids and chlorins (in particular, pheophytinand chlorophylls a and b) in SOM composition. Thus, results of CDF and content of chlorophylls a and b , pheophetins and carotenoids can be used to assess the postagrogenic transformation of SOM, and Margalef's PI-to characterize soil algocenosis.

For the landscape and climatic conditions of the Eastern European Plain fluvial processes are considered to be the leading geomorphic force during the Holocene. Different hierarchical levels of fluvial landforms from individual hillslopes through gully network to river systems are characterized by various degrees of resilience and relaxation times in response to external impacts of different duration, magnitude and frequency. These characteristics of fluvial systems largely depend on their spatial scale, effective discharges and morphodynamics. Particularly important is understanding of hydrological and geomorphic connectivity at various scales, rates and patterns of hydrological and sedimentary signals propagation and variable sources-pathways-sinks structure of geomorphic cascades under changing climate and land use conditions. It is generally accepted that landscapes of the European plains have experienced alternating periods of relative stability and significant shifts in climate, soil and geomorphological development over the Holocene. A number of studies has been devoted to the Holocene soil and gully erosion processes in Russia and other European countries. Available sources of information on the past erosion and deposition cycles in small catchments include truncated soils, completely or partially infilled gullies, colluvial deposits and lake or reservoir sediments. The highest temporal resolution may be derived from lacustrine sediments. Such geoarchives are characterized by continuous records and often store signals of landscape changes, surface dynamics and vegetation variability (including land use patterns for the historical period) in decadal to seasonal resolution. However, because of the problem of variable fluvial connectivity and associated limited sediment delivery in cascade fluvial systems, quantification of small catchment sediment budget can be a very difficult task requiring thorough consideration of colluvial deposits storages and remobilization.This study presents the new results of multidisciplinary reconstruction of interaction of geomorphic and soil-forming processes, landscape changes and stabilization phases during the Holocene for the Puzbol gully catchment (about 7.95 km2) draining the Borisoglebsk Upland northeastern slope towards the Nero Lake (Yaroslavl Region, central European Russia). The study is based on complex geomorphic, lithostratigraphic and soil surveys by means of detailed field description, photo-fixation, sampling and laboratory analysis of materials from >40 natural or artificial exposures, cores and soil sections. Observed absence of the early Holocene deposits can be explained by generally negative sediment budget of the catchment. It was more likely caused by high-magnitude low-frequency runoff events associated with climatic extremes rather than by dominance of continuous moderate erosion. A series of the middle Holocene 14C dates obtained by analyzing total organic carbon from humic layers of buried soils, lake gyttja and peats provides strong evidence of the synchronous phase of landscape stabilization in both upper and lower parts of the Puzhbol catchment accompanied by active infilling of smaller tributary gullies along its banks at middle part. The upper part of the Puzhbol Gully fan sediment shows clear evidence of synchronous accumulation of agrogenic colluvium and gully alluvium since XIIth Century on top of the Nero Lake terrace deposits.The study is supported by the Russian Science Foundation (Project No. 19-77-10061).

The hydrolytic and enzymatic degradation of polymer films of poly(3-hydroxybutyrate) (PHB) of different molecular mass and its copolymers with 3-hydroxyvalerate (PHBV) of different 3-hydroxyvalerate (3-HV) content and molecular mass, 3-hydroxy-4-methylvalerate (PHB4MV), and polyethylene glycol (PHBV-PEG) produced by the Azotobacter chroococcum 7B by controlled biosynthesis technique were studied under in vitro model conditions. The changes in the physicochemical properties of the polymers during their in vitro degradation in the pancreatic lipase solution and in phosphate-buffered saline for a long time (183 days) were investigated using different analytical techniques. A mathematical model was used to analyze the kinetics of hydrolytic degradation of poly(3-hydroxyaklannoate)s by not autocatalytic and autocatalytic hydrolysis mechanisms. It was also shown that the degree of crystallinity of some polymers changes differently during degradation in vitro. The total mass of the films decreased slightly up to 8&ndash, 9% (for the high-molecular weight PHBV with the 3-HV content 17.6% and 9%), in contrast to the copolymer molecular mass, the decrease of which reached 80%. The contact angle for all copolymers after the enzymatic degradation decreased by an average value of 23% compared to 17% after the hydrolytic degradation. Young&rsquo, s modulus increased up to 2-fold. It was shown that the effect of autocatalysis was observed during enzymatic degradation, while autocatalysis was not available during hydrolytic degradation. During hydrolytic and enzymatic degradation in vitro, it was found that PHBV, containing 5.7&ndash, 5.9 mol.% 3-HV and having about 50% crystallinity degree, presents critical content, beyond which the structural and mechanical properties of the copolymer have essentially changed. The obtained results could be applicable to biomedical polymer systems and food packaging materials.

The article, using the example of the Russian Federation, considers a number of environmental postulates that the authors consider to be the necessary condition and at the same time content for the successful implementation of the national environmental policy. The authors investigate the high-quality environmental law; effective working mechanisms for monitoring and supervising its compliance; and the inevitability of legal liability for violation of environmental legal norms.

In the current work, the degradation of poly (3-hydroxybutyrate) (PHB) and poly (3-hydroxybutyrate-co-3-hydroxy-4-methylvalerate) (PHB4MV) films was studied in vitro by pancreatic lipase. The changes in film properties were traced by several analytical methods: the change of weight, molecular weight, and Young’s modulus (by nanoindentation) were measured. During the six months of polymer films degradation the weight of samples decreased slightly, while a great increase in Young's modulus due to the relatively fast degradation of the amorphous areas was observed, as well as molecular weight of polymers decreased significantly. Weight loss of PHB4MV is faster than degradation rate of PHB, but the molecular weight of PHB 1700 decrease rapidly than PHB4MV; the Young’s modulus of polymers remained relatively unchanged.

According to radiochemical and biostratigraphic studies of the buried peat layer in the Cheremoshnik key section on the East European plain, the first age dating of this peat was obtained and its assignment to the Mikulino interglacial was confirmed. The Th/U isotope age data obtained for the peat horizon allow us to state with confidence that it was formed during the MIS5e. It was found that a variety of signs, including the lithological characteristics of dated layers and climatic indexes, is evidence that the Cheremoshnik site and Borisoglebsk upland occurred in the periglacial zone during MIS3–MIS2.

In the current work, we studied the degradation of PHB films in vitro by pancreatic lipase and in phosphate buffer saline (PBS). We traced the changes in film properties by several analytical methods: the change of weight, surface roughness and morphology (by atomic-force microscopy) and Young’s modulus (by nanoindentation) were measured.PHB is a semicrystalline polymer and thus the films have lamellar structure. During biodegradation, three types of changes were observed on the film surface: appearance of new lamellae, disappearance of lamellae and disintegration of lamellae into shorter fragments. During the six months of polymer films degradation the weight of samples decreased; and an increase in Young's modulus due to the relatively fast degradation of the amorphous areas was observed by nanoindentation.

The MIS3 paleosol units comprise a prominent element of the loess-paleosol sequences throughout the Eurasian Loess Belt. To the north of the loess regions, the findings of MIS3 paleosols were few: it was supposed that geomorphic processes related to the extensive ice cover of the Last Glacial Maximum destroyed the earlier soil mantle. Recently, much smaller extent of continental ice in the east of Northern Europe and ice-free West Siberian Plain during MIS2 has been hypothesized, supposing preservation of MIS3 and earlier paleopedological records. We discovered in the center-north of European Russia (Upper Volga basin) and Western Siberia (Middle Ob basin), MIS3 paleosols within the Late Pleistocene alluvial and lacustrine sequences and correlated the studied profiles on the basis of macro- and micromorphological characteristics and radiocarbon datings of the paleosol organic materials. Paleosols are represented by hydromorphic profiles with Histic horizons and gleyic color pattern. Conspicuously, they are developed in the well drained geomorphic positions, where modern soils are non-gleyic. We suppose that the presence of permafrost was responsible for water logging and generation of reductomorphic soil environment. We further hypothesize a northern zone of MIS3 soil mantle, comprised of Histic and Reductaquic Cryosols different from synchronous Cambisols and Chernozems formed within loess sequences to the south.

In the last decades, global warming has induced new trends in the dynamic development of the temperature and water regimes of soils. The main idea of the study was the search for soil identifiers of recent, regionally-specific climate changes occurring in the Volga River basin. Questions that were raised in the study: does recent climate changes find a response in soil properties of hydromorphic (waterlogged) soils of the southern taiga (1), what are the features of evolutionary trends related to ground water salinization in humid climate, as compared to other climate areas (2). This article describes climate-induced changes in properties of saline hydromorphic soils of the Nero Lake depression over the last 30–40 years. Our study focuses on changes in soil pH and contents of organic carbon, calcium carbonate and soluble salts. A comparative analysis of soil analytical data identified the following trends of soil development: desalinization, decreasing contents of soil organic carbon and total nitrogen, but increasing contents of hydrogenic calcium carbonate. Ecological factors of a regional scale which act on a specific territory correct the direction of global climate-induced soil tendencies in comparison to other saline continental depressions. At the same time the data obtained and identified tendencies largely confirm the prognosis for a global warming scenario alongside increasing humidity. Further research into unidirectional trends of soil development based on analyzing a large volume of data can allow for mitigation of influences of changing land use and a more precise detection of climate-induced processes of soil evolution.

Geoarchaeological and palaeopedological studies focusing on the reconstruction of the Holocene paleoenvironments require a detailed knowledge of the spatial variability of soil properties both for the surface soils and paleosols buried under archaeological constructions. However, such studies are often carried out at unique sites where it is difficult to ensure the representativeness of the data obtained. In this paper, we report original data on 15 soil profiles which shows the range of spatial variability of soil properties (рН H2O, рН KCl, particle size distribution, depth of genetic horizons, colour codes) for both surface and buried soils at the Tokhmeyevo kurgan cemetery, located in the Middle Volga region, Chuvash Republic, Russia. The data supplement the original research [1] and also give additional detailed information on pollen and spore analysis by plant species for the humus horizons in four buried and one surface soils. All soils developed from the same lithology (mantle loam), at the same elevation, in a similar topographic position (levelled upland slope) and in proximity to each other. Both buried and surface soils, classified as Retisols [1] , show slight variability in morphology and particle size distribution that varies in a similar range. However, the two soil groups (buried and surface) differ in two striking features: buried soils exhibit dark humus horizon and black humic cutans in the middle part of the soil profile; these features are absent in the surface soils. The values of рН in water and 1 M KCl suspension in the buried soils and soils of the kurgan mounds are lower than in the surface soils. The data on the spatial variation of the properties of the surface and buried soils increase the reliability of the results, making it possible to assess the extent to which the differences in soils are associated with the environmental evolution. The presented data can provide one the context for further work in paleoenvironmental studies and also be compared with other already published datasets increasing the reliability of conclusions about the trends of environmental evolution in the second half of the Holocene.

The method of chemodestructive fractionation is suggested to assess the composition of soil organic matter. This method is based on determination of the resilience of soil organic matter components and/or different parts of organic compounds to the impact of oxidizing agents. For this purpose, a series of solutions with similar concentration of the oxidant (K2Cr2O7), but with linearly increasing oxidative capacity was prepared. Chemodestructive fractionation showed that the portion of easily oxidizable (labile) organic matter in humus horizons of different soil types depends on the conditions of soil formation. It was maximal in hydromorphic soils of the taiga zone and minimal in automorphic soils of the dry steppe zone. The portion of easily oxidizable organic matter in arable soils increased with an increase in the rate of organic fertilizers application. The long-lasting agricultural use of soils and burying of the humus horizons within the upper one-meter layer resulted in the decreasing content of easily oxidizable organic matter. It was found that the portion of easily oxidizable organic matter decreases by the mid-summer or fall in comparison with the spring or early summer period.

The crystallization of calcium oxalates (weddellite and whewellite) by interaction of calcite marble with fungus Aspergillus niger , one of the most active stone destructors, was studied under in vitro conditions. The temporal development of acid production of fungus as well as the sequence of formation and morphogenesis of the growing oxalate hydrates crystals were investigated in detail. Furthermore, the relationships between morphology and growth conditions of crystals within the biofilms on the surface of carbonate rocks are discussed.

During the Holocene, interfluvial landscapes of European plains have experienced alternating periods of relative stability and significant shifts in climate, soil and geomorphological development. Assumed to be an arena of major transformation their evolutionary model is not entirely resolved yet. Based on lithostratigraphic, geomorphologic and soil survey, new results on the Holocene dynamics of fluvial and related processes including landscape stabilization phases for one of the gully catchments draining the Borisoglebsk Upland northeastern slope towards the Nero Lake are presented. Common absence of the early Holocene deposits can be explained by generally negative sediment budget of the catchment. Nevertheless, continuous erosion was not likely whether rare climatic extremes probably were the case. A series of middle Holocene dates obtained by analyzing total organic carbon from organic-accumulative layers of buried soils, lake gyttja and peats highlights strong evidence of the synchronous phase of landscape stabilization in both upper and lower parts of the Puzhbol catchment accompanied by active infilling of small erosion cuts in its middle part. The upper part of the Puzhbol Gully fan sediment shows clear evidence of synchronous accumulation of agrogenic colluvium and gully alluvium since XIIth Century on top of the lake terrace deposits.

Based on analyzing the catenary sequence of soils and parent materials down the northern slope of the Klin-Dmitrov Ridge adjacent to the Upper Volga Lowland (formerly the periglacial zone of the Russian Plain), it was revealed that sediments including sandy loams, clay loams and clays, which constituted slope terraces at heights from 130 to 180 m a.s.l. and often accounted for lithic discontinuities in soil profiles, had glacio-lacustrine genesis, i.e., they had accumulated during the existence of a periglacial dammed lake at the final stages of the Late Pleistocene.

The relationships between the electrical resistivity and the properties of hydromorphic saline soils forming in a humid climate were established. The salinity factor turned out to be the most significant for the value of electrical resistivity compared to soil texture and organic matter content.

A variety of studies of the re-examined (new exposure) Late Pleistocene key section Cheremoshnik (East European plain, middle of the Volga Basin of Yaroslavl) was conducted on a new methodological level using modern methods. For the first time, a series of paleosols (MIS5–MIS1) from the section offering significant information in regard to chronostratigraphy and landscape evolution have been studied in detail and dated. An excavation ∼7 m deep reveals a soil-sediment stratum which formed over the course of ∼115 ka in an accumulative beam-like terrace and consists of five lithological layers and six pedostratigraphical units. The base of the section was determined to be an Early Mikulino peat-dark humus paleosol which marked incipient subaerial pedogenesis on the Moscow (Riss II) moraine and was covered with a thickness of gyttja with a peat horizon (Histosol) which had formed 114–115 ka and was reliably dated using uranium–thorium dating. The following paleosols were successfully identified within the series of weak stone gullied-channel sediments within the Valdai (Wűrm) thickness (from bottom to top): (1) Bryansk paleosol (MIS3) – Gleysol – with three pedogenesis rhythms; (2) Trubchevskaya paleоsol – Gleyic Turbic Cryosol (MIS2) and (3) pedosediment formed at the end of the Bӧlling interstadial (MIS2). Terminal Pleistocene formations are marked with a gravelly stratum on the section's surface formed during the Preboreal period. Recent Regosol formed on loess-like loam deposits was identified at the top of the whole soil-sediment stratum. The 14C age of the paleosol humus varied between 27,500 and 11,400 cal. BP. The paleosols represent the northernmost occurrence of MIS5–MIS2 fossil soil in Europe, dominated by features of gleyzation, cryogenic aggregation, cracking, and humus and peat formation. Pollen analysis results allowed estimation of changes in vegetation cover, climatic conditions and the age of deposit sedimentation for the period from the Moskow Late Glacial to the Valdai Late Glacial and early Holocene times. Successive stages in the development of vegetation, high contents of alder and hazel pollen and the climax and distinct appearance of broadleaf trees relate the formation of biogenic sediments (LPAZ 2–6) in the Cheremoshnik section to the Mikulino Interglacial. Valdai (MIS4–MIS2) glacial sediment is absent within the investigated area.

Late Holocene landscape evolution at the southern frontier of the forest belt of European Russia is studied based on detailed morphological, analytical and microbiomorphic research of a soil chronosequence that included a surface soil and a soil buried under the Bronze Age kurgan. Both soils (Folic Eutric Cambisols) are formed on similar geomorphic surfaces in the same parent material and in close proximity to each other. The soil morphology and the key analytical features are controlled by low-reactive parent material and imply close similarity of the present landscapes and those of the Bronze age. At the same time the morphological features show that the buried soil was influenced by the phase of weak aridization, which led to the formation of a dark mull humus horizon. Microbiomorphic assemblages (phytoliths, pollen) support the earlier conclusion that the soils of the study area had being developed mostly under forest vegetation.

Buried Late Holocene paleosols of the Nienshants historical monument at the junction of the Neva and Okhta rivers (St. Petersburg) have been studied. These soils developed from estuary deposits of the Littorina basin with abundant artifacts of the Neolithic and Early Iron ages (7–2 ka BP). The soil cover of the area consists of the mature dark-humus profile-gleyed soils on elevated elements of the mesotopography (3.0–3.5 a.s.l.) and dark-humus gley soils in the local depressions (2.0–2.6 m a.s.l.). The soils are characterized by the low to moderate content of humus of the fulvate-humate type. The beginning of humus formation in the dark-humus gley soil on the slope facing the Neva River is estimated at about 2600 yrs ago; for the darkhumus profile-gleyed soils of the studied paleocatena, at about 2000 and 1780 yrs ago; and for the darkhumus gley soil, at about 1440 years ago. Judging from the spore-pollen spectra, the development of these soils took place in the Subatlantic period under birch and pine-birch forests with the admixture of spruce and alder trees. The gleyed horizons of the buried soil at the depth of 1.6–1.2 m on the Neva-facing slope date back to the Late Subboreal period (2500–2600 yrs ago), when pine-birch-spruce forests were widespread in the area. The new data contribute to our knowledge of the environmental conditions during the Neolithic and Iron ages.

Two paleosol-sedimentary sequences Koskovo and Puzbol developed within the nearest periglacial zone of Valday glaciation of the East European Plain (56.7°–58.5° N, the Upper Volga River basin) were studied to reconstruct soil mantle and landscape evolution since Marine Isotope Stage (MIS) 3. The sequences are formed on terraces at 130–141 and 172 m a.s.l., constituted by ancient (Early Valday (Wurm) or Late Moscow (RissII)) lake clayey sediments. The buried paleosols are represented by system of horizons Hb–G3b (Histosol), Agb–G3b and AGb horizon (Umbric Gleysol). The 14 C age of the paleosol humus and peat varied between 50,300–39,700 cal. BP. These paleosols were developed under forest-tundra and pine-spruce forests with the meadow plant communities and the areas of swampy vegetation according to palynological data from Puzbol. They represent the northernmost occurrence of the MIS3 fossil soil in Europe dominated by the features of gleyzation, cryogenic aggregation, cracking, and humus and peat formation. Clay coatings in the Middle Valday paleosols and pedosediments are products of Holocene pedogenesis. The upper lithological layers covering the MIS3 paleosols are loess-like (mantle) loams underlain by clayey Late Pleistocene lake deposits. They mark the presence of wide extraglacial lakes with existed within the Upper Volga basin during the maximum advance of the Valday glaciation (MIS2). Based on the stratigraphy of the studied sections, the highstands of these Late Quaternary lakes might exceed ≈170 m a.s.l. For the first time it was possible to date the age of humus-clay coatings developed in the Bthk3 horizon (c.1.6–2.0 m) of Puzbol where in the upper part of the section the Cutanic Albeluvisol formed. The Early Middle Holocene age of humic acid of humus-clay coatings (≈10,900 cal. BP) and carbonate nodules 7500–8180 cal. BP refer to the first stage of pedogenesis of this polygenetic soil, which occurred from pre-Boreal to the Atlantic period, and was characterized by dark humus accumulation and carbonate precipitation in a poorly drained landscape. The 14 C age of the fulvic acids of these coatings (≈6130 cal. BP) is indicative of the beginning of the second stage, dominated by clay illuviation under a better drained, leaching environment.

According to the results of screening acidification activity of 24 species of micromycetes in vitro, 18 of them produced organic acids in artificial medium. The fungi from genera Penicillium and strains of Aspergillus niger have the most active production of organic acids. The ratio of acids formed by fungi on a liquid glucose-containing medium changes during ontogenesis: gluconic acid and acids of the Krebs cycle dominated in a log phase of growth; oxalic acid accumulated in a stationary phase while concentrations of other organic acids reduced. Oxalic acid is the main acid produced by fungi in a culture and apparently in a natural habitat. Formation of gluconate improves the efficiency of other carbon substrates consumption by fungi. Citric, succinic, malic, and fumaric acids are produced only at higher concentrations of carbohydrate and high ratio of C/N. Production of oxalic acid by micromycetes increases on the media containing only nitrate nitrogen. Zn in concentration up to 2 mM induces secretion of oxalic acid on nitrate media. Copper has stimulation effect on oxalic acid production only in very low concentration (25 µM). Presence of Zn in culture leads to formation of oxalate Zn crystals on the surface of mycelium. On ammonium-containing culture Zn and Cu does not stimulate oxalic acid production, but induce significant morphological changes.

A sequence of five paleosol units (with seven individual paleosol profiles) buried in the Late Pleistocene (20–40 ka) deposits was studied at the Kostenki 14 (K14) key section in Voronezh oblast with the use of a set of morphological, physicochemical, and instrumental methods. The upper-lying paleosols differed from the lower-lying paleosols in the less pronounced gley features, stronger aggregation of the soil material, more significant accumulation of carbonates, and higher percentage of calcium humates and fulvates. These features attested to the higher aridity of the paleoclimate and the development of the upper-lying paleosols under grassy vegetation. Within the studied paleosol sequence, the most developed profiles were typical of the soils that formed 27–32 ka ago during the Bryansk interstadial. The good aggregation, the presence of features left by the soil fauna activity, the high magnetic susceptibility, and the morphology of the secondary carbonates in the studied paleosols suggest that they were formed under meadow-steppe vegetation in well-drained positions and resembled modern cryoarid soils.

The physical and physicochemical properties and morphogenetic characteristics of the buried soddy gleyic and gleyed paleosols developed from the glaciolacustrine loamy sediments on the southern coast of the Finnish Gulf in the Late Pleistocene and Early Holocene (12–9 ka, calibrated) are considered. It is shown that the morphology and properties of these paleosols sharply differ from those of the enclosing gravelly sands deposited in the ancient basins. The latter substrates serve as the major type of soil-forming materials for the modern surface soils. The studied paleosols fill wedge-shaped structures dissecting the gravelly sediments. Their profiles are well preserved, though their normal horizontal orientation is disturbed; large soil blocks were displaced into the open wedges. The presence of these soils attests to the fact that the initial soil cover in the studied region was formed in the Late Glacial epoch soon after the retreat of the glacial sheet. The good degree of preservation of the paleopedogenic information recorded in the profiles of these paleosols is of great value for the paleoenvironmental reconstructions.