An Erratum to this paper has been published: https://doi.org/10.1134/S1028334X23070115

Application of geological geomorphological and geochronological (14C, OSL) methods allowed to establish that the bordering mountains of the Chuya basin (Russian Altai) were affected by glaciation already in the Middle Pleistocene – about 160–180 ka ago (MIS 6). However, the maximal ice-dammed lake with the highest (up to 2100 m a.s.l.) strandlines both in the Chuya and Kurai basins existed later than 90–80 ka ago, in the Late Pleistocene. This chronological benchmark limits the influence of the cataclysmic outburst floods from the largest ice-dammed lakes on the accumulation of the Inya formation in the Chuya and Katun river valleys. It is confirmed that a large ice-dammed lake existed and had a water level of at least 1730 m a.s.l. in MIS 2 in the Kurai basin. It was drained no later than 16 ka ago. Synchronously (about 17–16 ka ago) the accumulation of diluvial-lacustrine cyclites began in the Inya mouth. The Saldzhar formation had been depositing as a result of not only flood events, but also gradual hydrological processes in the Katun river valley between the mouths of the Chuya and Sema rivers during the entire MIS 2. It is necessary to revise the concept adopted by SibRISC in 2018. This concept assumes i) absence of ice-dammed lakes in intermountain basins of the Russian Altai in MIS 2 and ii) accumulation of the Inya and Saldzhar formations deposited by glacial megafloods in the valleys of the Chuya and Katun rivers before 90 ka ago.

Assessing the variability of stable carbon isotope composition in Cambisol organic matter is important for understanding the response of forest soils to environmental changes. The studies were carried out in the foothills of the northeastern macroslope of the Eastern Sayan Ridge. For the first time, the formation of Cambisols was proved there. Investigated soils are among the isotopically lightest soils in the Baikal region, which is most associated with favorable moistening conditions for the vegetation that forms soil organic matter (δ13С values of the dominant species vary from –32.6 to –27.8‰). Variations in δ13С values from site to site do not exceed 1‰ (–25.81…–26.81‰) for the organic matter of surface soil horizons despite significant differences in the input and subsequent transformation of organic matter. At the same time, a significant soil profile gradient of δ13С values (4–5‰) is registered. The analysis of differences in the intensity of carbon turnover expressed through the slope of the linear regression (β) between δ13C values and log-transformed content of total carbon in the soil, which varies with depth, showed that, most likely, the isotopic depth-profile of the studied Cambisols is formed under the influence of microbial utilization of organic matter, which is manifested having different intensity depending on the composition of organic-rich horizons. The increased intensity of mineralization of labile components of plant material in the upper part of the organic profile of soils with developed litter and organic-accumulative horizons can lead to a noticeable increase in δ13С values and a more pronounced β, in contrast to soils with a predominance of mineral horizons in the organic profile.

Cryoaridic soils were proposed to be identified as an individual genetic soil type by Vladimir Volkovintser in the 1970s. Volkovintser argued that the specific properties of these soils are in good agreement with the soil-forming factors: ultracontinental climate, cryoxerophytic steppe or tundra-steppe vegetation, dry permafrost, and skeletal parent material. In cryoaridic soils, the properties of chestnut and pale soils are combined, but their individual features are due to the specific cryohumus AK horizon and secondary carbonates dominated by pendants. Cryoaridic soils were not included in the soviet soil classification system of 1977; in the Russian soil classification system, the type of cryoaridic soils with the AK–BPL–BCA–Cca horizons is included in the order of pale-metamorphic soils with the pale-metamorphic BPL horizon as diagnostic for all soil types of this order. However, our field research, analysis of publications, and the study of soil in the Central Soil Museum give us grounds to verify diagnostic criteria, to change the profile type formula of cryoaridic soils, and to review their taxonomic position in the classification system. We argue that the BPL diagnostic horizon should be replaced by the diagnostic property (pl), which means that cryoaridic soils should be transferred into another order, presumably, the order of humus carbonate-accumulative soils. Some additional subtypes are proposed. On highly skeletal shallow parent materials, cryohumus soils belonging to the order of organo-accumulative soils are developed.

The tumuli of the Koy-Gunzhar burial ground (2400-2000 cal years BP) in the North Kazakhstan are monumental earthen mounds, built in honour of the Scythian elite. The tumuli, besides repre-senting the diversity of the building techniques for such earth burial mounds, also provide a unique opportunity to study the direction and character of the paleosol diagenesis for nearly 2400 years. This soil-archaeological study aimed to reveal mound building techniques, the characteristics of materials used for construction, and diagenetic changes of the buried paleosols. The comparative analysis of tumulus embankments and buried soils (their genesis and diagenetic transforma-tions) provided the opportunity to establish the source of the building material and to reconstruct some details of the building technologies. For instance, the Calcic Someric Kastanozem (Arenic, Protosodic), buried by loam-sandy and sandy sub-strate of the tumulus 3, corresponds to dry steppe conditions and has no considerable signs of diage-netic transformations, whereas the paleosol under the tumulus 1 was affected by strong diagenetic transformation supposedly due to acid drainage from the embankment which originally contained sulfidic material being subjected to oxidation and acidification after the tumulus construction. Diagenesis was manifested in the redistribution of pedogenic carbonates and enrichment in iron, magnesium, manganese, and aluminum compounds in the upper 32 cm of the buried soil. These elements were partially accumulated at the carbonate geochemical barrier (over Bk horizon of the buried soil). This soil was transformed by diagenesis from Kasrtanozem to Mollic Cambic Umbrisol (Epiloamic, Katoarenic). The builders of the tumulus 1 used a loamier substrate to con-struct the mound, different from the parent mate-rial for adjacent soils (loamy sands and sands). The loamier substrate ensured the firmness of the mound construction. The builders employed an uncommon technique to produce a mound with defined properties and used foreign building materials brought from the distance.

This research compares results of micromorpholog-ical case studies conducted on four early medieval archaeological sites with differentiated spatialization of human impacts and a varied craft production located in different background environments: humid climate, subzone of mixed forests, floodplain of the Dnieper River (Gnezdovo site); semi-humid climate, subzone of forest-steppe, Middle Volga region (Muromsky Gorodok and Malaya Ryazan' sites); arid climate, cold desert of the Aral region, ancient delta-alluvial plain of the Syr-Darya River (Dzhankent site). Micromorphological studies of habitation deposits revealed clear geographical and geochemical regularities in the occurrence of geo-genic (soil, sedimentary and post-sedimentary) fea-tures. Intrasoil migration and accumulation of clay and coarser silicate material in textural pedofeatures were described in cultural layers of sites located in forest and the forest-steppe zones. An anthropogenic input of phosphates provokes simultaneous migration and illuvial accumulation of phosphates and clay. In the habitation deposits in steppe landscapes with calcareous lithology, the key background soil pro-cess is redistribution and intrasoil accumulation of calcium carbonates. In the alluvial desert landscape, major soil processes are accumulation of gypsum and readily soluble salts. All layers are or were affected by at least some seasonal over-moisturizing that resulted in a variety of redoximorphic features depending on their palaeo-and/or contemporary water regime. The high variety of anthropogenic processes and corresponding microfeatures was grouped as follows: (1) input, output, turbation, compaction; (2) neofor-mation and migration; (3) pyrogenic processes (prod-ucts); technological processes (products). The set of anthropogenic features records past human impact in the locality. The higher the variety of anthropogenic features and their general abundance is, the more intensive and variable the human impact which had occurred in the past. At the same time, the occurrence of certain anthropogenic features may indicate not only human-related processes of their formation (or input), but also a contemporary soil environment. This environment can be favorable, or, in the oppo-site, deteriorative for earlier formed anthropogenic features.

Paleopedology, the study of soils developed on ancient landscapes (Yaalon, 1971), was born in Russia through the efforts of Boris B. Polynov (1927), but considering the previous work done by Vasilli V. Dokuchaev in 1883 (Dokuchaev, 1967) and later with the support of Constantin C. Nikiforoff (1943). The Commission on Paleopedology was established in 1965, in Denver, USA, by Dan Yaalon and Hans van Baren (Retallack, 2013) during the 7th Congress of the International Association for Quaternary Research (INQUA) and later, in 1968, the Commission was affiliated to the International Union of Soil Science (IUSS). After the Denver conference, the Commission published a volume with research papers focused on the recognition and classification of paleosols, methods of dating, and soil stratigraphy (Yaalon, 1971). This volume was the beginning of an extensive series of the Commission publications in different special issues of international and national scientific media. Two of these collections were published in open-access Mexican geological journals: Revista Mexicana de Ciencias Geológicas v. 20 no. 3 (2003) and v. 21 no. 1 (2004), and Boletín de la Sociedad Geológica Mexicana, v. 64 no. 1 and 64 no. 2 (2012). The current issue is a continuation of this series. There are two concepts necessary for understanding paleosols. The first is the use of the uniformitarian principle, which suggests that past geologic processes are similar to those acting today on the Earth’s surface. In other words, the basis of modern soil geography and soil genesis is used as directly analogous to reconstruct ancient environments and landscapes. This approach is more precise when applied to Quaternary paleosols and more limited to pre-Cambrian or Paleozoic paleosols, as the environmental conditions under which they were formed are pretty different from the modern ones (Retallack, 2001). The second concept is “soil memory” (Targulian and Goriachkin, 2004), related to a set of properties that can remember ancient environmental conditions. These properties result from pedogenetic processes and soil-forming factors and are time-resistant to environmental changes remaining stable during extended periods (Targulian and Goriachkin, 2004). In recent years, paleopedology has extended its applications to reconstruct past climates, establish variations in the atmospheric composition, trace the ecosystem evolution, and identify geomorphological changes (e.g., Cerling, 1991; Retallack, 1998, 2009; Goudi, 1990; Klinge et al., 2022). Some efforts have also been made to develop models to quantify pedogenetic trends associated with environmental change (e.g., Yaalon, 1975; Sheldon and Tabor, 2009). An essential application of paleopedology has been devoted to solving archaeological problems, as soils can be considered repositories of human activities: agriculture, forestry, material for construction or ceramic production, dwelling and householding (Holliday, 2009; Costa et al., 2021; Yalçın et al., 2021). The impact of past anthropogenic activities has been recorded in the soil memory through time: since the first hunter and gatherers groups to the industrial societies. However, the relationship between humans and their environment (and vice versa) is complex and demands the application of different methodologies and the study of in-site and off-site approaches (Butzer, 2008), which integrates the information directly recovered in the archaeological excavation and that from the surrounding areas. In this sense, the paleosol-archaeological investigation has a more solid interpretation. In June 2021, the Paleopedology Commission of the IUSS, the Paleopedology Working Group of the INQUA, and the Institute of Geology of the UNAM organized a three-day online meeting with scientific sessions. The meeting topics related to the link between paleosols, the history of human interactions, and the environment. This special issue was launched as a result of this meeting. The articles included here aim to improve our understanding of the materials used for ancient constructions also past human interactions with the environment.

In this study we investigated different age carbonate coatings in the surface steppe and forest-steppe soils and paleosols of the Baikal region and its relationship with environmental fluctuations of the Late Pleistocene and Holocene. The C-14 age of thin pedogenic carbonate laminae indicate four periods of coating formation: the second half of MIS-3 (24.1-23.3 and similar to 34.0-35.0 kyr BP), from the warm phases of the Late Glacial to the Middle Holocene (12.9-4.6 kyr BP) and the final of the Middle Holocene (3.6-3.3 kyr BP). Thus, studied carbonate coatings are mainly relict feature of the previous epochs of pedogenesis and Middle Holocene stage of surface soil formation. Paleoecological conditions reconstructed for the identified stages of formation of carbonate coatings correlate well with the trend of climatic changes in the Baikal region and adjacent areas. They reflect the effect of temperature and moisture fluctuations on the dynamics of soil-forming processes. Distinct delta O-18 and delta C-13 values suggest that the coatings of Transbaikalian steppes and forest-steppes of Fore-Baikal region have been formed under contrast environmental conditions. It is assumed that the formation of pedogenic carbonates in Transbaikalia is mainly confined to the summer season, when the soil is most warmed up, and the plants actively consume water and emit a large amount of CO2 . This agrees well with the slightly higher temperatures of the warm season and the greater aridity of this region. In turn, carbonate precipitation in Fore-Baikal region occurred during the degassing of soil solutions in the course of periodic freezing and thawing, alternation of phases of snowmelt and rainwater infiltration into the soil and its subsequent freezing, which can be observed in the region in spring and autumn. A significant CaCO3 content in the studied soils contributed to the high growth rates of pendants. Holocene coatings are characterized by maximum growth intensity, which correlates with the highest carbonate content in the slope sediments where they are found. At the same time, MIS-3 coatings formed mainly on significantly less carbonate-rich alluvial deposits, which apparently affected their lower growth intensity. Based on an analysis of the growth rates of coatings, comparison of the isotopic composition of different age groups of pendants and soil micromorphology the more humid climatic conditions of the MIS-3 is assumed in comparison with the Middle Holocene. The temperature conditions of pedogenesis may be similar. Both for the Middle Holocene and for the MIS-3 relatively low temperatures of pedogenesis and long-term seasonal soil freezing are supposed.

Anthropogenic soils and soil-sedimentary systems (cultural layer, occupation deposit) in settlement archaeological settings are highly valuable and underappreciated archives of past environments, land-use activities, and life cycles within past residential areas. This study is aimed to reconstruct fire history for the early medieval town of Dzhankent located in Eastern Aral region, Kazakstan as based on the C14 dated stratigraphy, morphology and micromorphology, data on charcoal morphology, C:N and C13 isotope records. Several sections of cultural layers were studied within excavated areas. Stratigraphic units were thoroughly C14 dated (58 dates). Most 14C dates are between the 7th and 10th centuries, and most of the dates have overlapping intervals of calibrated age although clear up-section trends from older to younger ages may be seen. This demonstrates the slow, progressive accumulation of occupation deposits. The analysed excavation sections are very well stratified. Stratigraphic units based on char-enriched marker beds could sometimes be traced for long distances. Char enriched layers contain enormous quantities of both grass and wood charcoals. Thin, about 1 m long lenses of ash and charcoals of poor and unified taxonomic variety are thought to be fireplaces. Extended thick char-enriched layers (about 10 meters long and 0,1 m thick), well stratified at macro-, and micro-levels, with sub-parallel oriented charcoals of highly variable taxonomic compositions considered to be traces of big fires. Three fire events were detected based on the stratigraphy, morphology, charcoal amounts, C, N and C13 isotope depth variability. Filed studies and were funded by DFG project 389351859. The analytical part was supported by RFBR 19-29-05238, and DFG 389351859.

A complicated tectonic and sedimentation history of the high-mountainous south-eastern part of Russian Altai predetermined the presence of sources of ancient organic matter in the region. During the Pleistocene these deposits were affected by various exogenous processes that leads to mixing of young and old carbon in a unique (for each sample) ratio and strongly affects the results of radiocarbon dating. This paper presents the results of multidisciplinary investigations of pedosedimentary sequences and discusses C-14 dating of heterochronous organic matter in paleosols of two locations within the Chuya basin in the chronological context of the late Pleistocene megafloods. In the Kamsug valley reasonable evidence of the oldest (Pleistocene) paleosols in the SE Altai is described for the first time. The mineral composition of sediments and the results of pollen analysis argue for a short-distant redeposition of the Paleogene-Neogene parental substrate. Later it was transformed by Pleistocene pedogenesis: cryogenic processes, particularly solifluction, redox fluctuations resulted in redistribution of Fe and Mn. The analysis of available radiocarbon dates indicates that the contamination of the samples by extraneous carbon and the insufficient data about the features of organic matter of the studied soils don't allow to draw a definite conclusion about the time of the Pleistocene pedogenesis in the region. The presented OSL age 37.0 +/- 3.1 ka (GdTL 3424) predates pedogenesis in this location, as well as the last ice-dammed lake formation in the Chuya basin and its further cataclysmic draining followed by the deposition of cross-bedded gravels and pebbles. In the neighbouring Yamanterek valley radiocarbon dating result for paleosol returns erratic (aged) date due to the influx of ancient organic matter. Similarly, this date cannot serve as the upper chronological limit of ice-dammed lakes existence in the Chuya depression. The radiocarbon ages (9.7-11.3 ka cal BP) of charcoals from the underlying lens of humus sands postdate the last ice-dammed lake with the water level at least 1980 m a.s.l. It was demonstrated that short-distant redeposition of the Paleogene-Neogene sediments in the region preserves their main mineralogical and paleontological features. It gives an opportunity to recognise such redeposited sediments which contain geological carbon. Meanwhile the redeposition followed by pedogenesis introduces younger organic matter. Diagenesis of such originally different organic matter contributes the final pool of organic carbon and results in the formation of heterogenous and heterochronous organic matter. This should be taken into account while 14C dating and interpreting the obtained results.

The high mountainous southeastern part of Russian Altai is characterized by complicated sedimentation history. As a result of tectonic movements, Paleogene, Neogene, and even more old Carboniferous and Jurassic organicrich deposits had been partly uplifted and exhumed on the ridge’s slopes, where during the Pleistocene, they were affected by various exogenous processes including glaciation, glacio-fluvial erosion, winnowing activity of ice-dammed lakes, sliding during lake-draining events, followed by further intensive Holocene erosion, pedogenesis, and permafrost formation/degradation. Remobilized ancient organic matter had been involved into geomorphic and pedogenesis processes and affected the results of radiocarbon dating. Numerous radiocarbon ages obtained revealed several typical problems in interpretation of dating results, which was confirmed by multidisciplinary investigations of associated sediments in a wider regional context. This article presents a discussion on obtained apparent radiocarbon dates of organic material from ten sections of the SE Altai. In addition to radiocarbon analysis, in each case multidisciplinary study was carried out in order to properly interpret obtained dates, as well as to explain the inability of directly using apparent 14C ages as a geochronological basis for paleogeographical reconstruction. The analysis presented is of vital importance for establishing the chronology of formation of large ice-dammed lakes and their cataclysmic draining; revealing chronology and paleoenvironmental conditions of pedogenesis in the highlands of the SE Altai; and estimating the range and magnitude of the tectonically driven topography rebuilding in the post-Neogene time.

A series of 63 14C dates were obtained from non-destructive core-drilling across the Dzhankent site (the early medie- val town located in Eastern Aral region), a second series – 58 dates from stratigraphic sections within excavated areas. Most of 14C dates are between the 7th and 10th centuries; clear up-section trends from older to younger ages may be seen. The analysed excavation sections are very well stratified. Stratigraphic units based on char-enriched marker beds could sometimes be traced for long distances. Extended thick char-enriched layers are considered to be traces of big fires, while small lenses of ash and charcoal are thought to be fireplaces.

The current state of knowledge on the problems of soil memory is highlighted. A brief review of recent publications concerning soils as information systems, soil behavior in time and space, and reconstruction of the environment based on soil records is given. Theoretical basics of the concept of soil memory as a soil capacity to record the environmental factors and soil forming processes in a set of stable features in the solid phase of the soil body are discussed. Mechanisms of recording, accumulation, and storage of this information, its particular carriers, and methods of their study are considered. Two major models of soil memory and distribution of records in a soil profile in response to evolutionary changes in the environment and soil are suggested in dependence on an increase or a decrease in the pedogenetic potential of climate and biota. A notion of geosystem memory is introduced. The blocks of geosystem memory are discussed in a hierarchy from a subsystem level to a level of particular discrete objects. Environmental proxy indicators for each block of geosystem memory are listed. Further prospects for the development of the concept of soil memory are seen in widening of a set of methods applied to study the solid-phase soil matrix and in linking the studies of particular components and elements of a soil body with its hierarchical morphogenetic analysis.