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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.

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 southern steppes of European Russia are rich in archaeological monuments that were extensively studied for many decades. Nevertheless, paleosols buried under the burial mounds and especially the big kurgans of the Bronze Age in the Ponto-Caspian area did not receive proper attention. The paper focuses on soil evolution and climate dynamics during the Bronze Age based on the study of soils buried during several stages of earthen mound construction within one big kurgan in the Kuban-Azov Plain, Russia. The kurgan 1 in the Beysuzhek-9 kurgan cemetery of the Bronze Age, situated in the Korenovsky District, Krasnodar Region, consists of three earthen mounds made at different times. The soils, buried under three mounds of the kurgan, are located in close vicinity from each other and have similar lithology and geomorphic position. They form a chronosequence representing three time slices. Moreover, the chronosequence displays a certain chronological order of burial: paleosols were first buried in the center of the kurgan and later closer to its periphery. The height of the kurgan is about 4 m that ensures good preservation of the buried soils. The research is based on the comparative analysis of morphology, micromorphology and analytical properties of three paleosols buried under different constructions in the kurgan and surface soil. Also, the palynological analysis was performed for the uppermost layers (0–5 cm) of three paleosols. During the first stage of the kurgan construction, the Novotitorovo archaeological culture of the Early Bronze Age at the 27th-22nd centuries BC, the climate of the region was sufficiently humid and provided a high bioproductivity for surrounding landscapes. The interval between the second and third stages of kurgan construction was marked by the gradual increase in aridity. During the third stage of the kurgan construction (the Catacomb archaeological culture, the Middle Bronze Age, the 21st −16th centuries BC), the climate was mostly arid. The results of the palynological analysis are in agreement with the study of paleosols. During the construction of the kurgan, the vegetation pattern corresponded to a Southern forest-steppe. The percentage of herbaceous plants increased markedly, and steppe species appeared during the time of Catacomb culture.

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.

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.

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.

The article presents information about of the work of the International Scientific School on Paleopedology for Young Researchers. This school was conducted for ten years in Siberia in the Altai region, where unique Pleistocene loess-soil series are common and paleosoil horizons and modern soils are present simultaneously in one and the same soil profile. For ten years leading Russian and foreign scientists gave lectures both on fundamental theoretical and applied issues of paleopedology, as well as on a number of topical issues of related sciences, conducted master classes on the basic methods of field study of paleosols, and young researchers discussed their ideas and results. The article lists the main themes of the lectures/ naming Russian and foreign scientists who read them. It also informs about the monograph “Paleosols, the natural environment and methods for their diagnosis”, based on selected lectures at the School from its start until 2014 and published in Russian. Other selected lectures were published in two languages (Russian and English) in the series “Paleosols – a source of information about the Past environment”. The aricle draws attention to the key site "Volodarka" as being of great importance not only for conducting field master classes, but also as a convenient training ground for scientific research, since there occur various soil environment that can serve as models created by nature itself.

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.

Vladimir Opolie is a typical loess island with soil pattern that differs strikingly from that of adjacent territories. Soils are characterized by a controversial set of features. They have common features with other loess islands located in various environmental zones (similar dependence on microtopography with second humus horizons in soils within depressions and accumulation of carbonates in soils on the main surfaces). On the other hand they differ from soils of loess islands formed on typical loess due to specific features of sediments: mantle loams, and a northern variety of loess. A pedostratigraphic approach to the study of soils of Vladimir Opolye reveals that constitution of the upper loess strata depends on paleocryogenic microtopography and that relict soil features (second humus horizon, pattern of carbonates distribution) are syngenetic with the final stages of loess sedimentation. The abundance of relict features indicates that the soils of Vladimir Opolie are surface paleosols.

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.

A new super deep penetration (SDP) method of polymer nanomembranes production was developed. Its advantages as compared to nuclear methods were discussed. They are connected with simplicity and low price of SDP application. SDP method implies the use of explosion for track membranes forming. As a result, a plurality of holes are formed in polymer matrixes. Removal of the residual particles of water-soluble salt is done by washing the pierced membrane with water.

The study of Upper Permian paleosols in the eastern part of the Russian Plain enables us to consider general problems, like interrelation of pedogenic and lithogenic memory, the development of Pre-Quaternary loess-paleosol series, the use of red beds as a paleogeographic archive, the paleoenvironmental reconstructions based on the study of paleosols, pedostratigraphy, and the relationships between pedogenesis and sedimentation.

Study of the upper loess strata within the profile of surface soils highlighted the role of pedogenesis in the formation of characteristic features of loess. Loess-paleosol sequences within the study area are influenced by their position in paleocryogenic microrelief. Clear evidence of sequential loess sedimentation, accompanied by slope processes and pedogenesis, is present in soil profiles within former thermokarst depressions. Different stages of loess sedimentation are marked by cryomorphic features, solifluction stripes and buried humus horizons. The balance between the rate of sedimentation, intensity of slope processes and pedogenesis changed within the upper 3 m of loess strata. Corresponding loess strata in inter-depression areas were also formed by sequential accumulation of aeolian dust, gradually altered by initial pedogenesis that left weakly developed soil profiles without clear horizonation. Pedogenesis resulted in diverse complexes of secondary carbonates, loose soil fabric and microfabric with abundant pores of biogenic and cryogenic nature, as well as other features, characteristic of soils of cold arid environments. The uniformity of these features throughout the upper loess strata confirms the synlithogenic nature of pedogenesis that accompanied loess accumulation.