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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.

The research highlights the foundations of a new quality of education formed by transforming the institutional environment. The study's methodology is a complex of approaches, revealing in interrelation the philosophical aspect of the formation of the foundations of the new quality of education - including systemic and personal-activity approaches; logical and historical approaches; qualitative and quantitative approaches; phenomenological and ontological approaches. The foundations of a new quality of education formed by transforming the institutional environment based on the philosophical aspect are proposed to be divided into two groups: objective and subjective foundations. Objective foundations have an impact on the education quality while not being conditioned by the institutional environment. Subjective foundations, on the contrary, are in a direct causal relationship with it. We consider it necessary to single out Informatization and Integration of Society among objective foundations. As subjective foundations, we single out Quality Assurance and the Dynamics of Interests of all participants in the educational, research, entrepreneurial and innovative processes. Subjective foundations are proposed to be considered in the European term Quality Culture structure.

Following a major revision of the Sartan ice sheet limits, Velichko et al.’s (2011) view of northwestern Siberia as a cold arid desert during MIS 2 (27.8–11.7 ka) has been prominent in regional scholarship. Our article presents the analysis of a series of sandy sediments associated with MIS 2 polygonal ice-wedge pseudomorphs (PIWPs) located in the Lower Nadym, the Middle Nadym, and the Siberian Uvals regions. Whereas Velichko et al.’s cold desert hypothesis was based on optical morphoscopy, our research relied on the scanning electron microscope technology (in conjunction with sedimentological, soils, and radiocarbon data). Our morphoscopic analysis of three wedge fill – host sediment pairs suggests that none of the MIS 2 surface sediments can be unequivocally associated with desert dune environments, but instead resemble alluvial deposits that have been moderately to substantially reworked by aeolian and cryogenic (freeze-thaw) processes. While the environmental characteristics varied between different sub-regions, northwestern Siberia likely resembled a sparsely vegetated tundra during MIS 2. AMS radiocarbon dates obtained from the organic matter of paleosols discovered inside of PIWPs indicate that the climate warming in northwestern Siberia began around 13.5–13 ka cal BP (end of MIS 2). This climatic shift was associated with a more pronounced warm season, as evidenced by the surface sediments experiencing more intensified freeze-thaw cycles in all of the examined locations. Judging from our analysis of sandy deposits, aeolian activity intensified in the Siberian Uvals in the middle MIS 2, compared to early MIS 2. Aeolian activity also intensified in the Middle Nadym in the second part of MIS 2, compared to the first part of MIS 2. Besides the intensified freeze-thaw processes at the end of MIS 2, surface deposits of the Lower Nadym region remained relatively stable throughout the Sartan cryochron.

The Gulf of Mexico coastal plain contains one of the largest dune systems in Mexico. These dunes and particularly their paleosols contain valuable paleoenvironmental information, however this aspect has been poorly studied. Here, we present the preliminary results obtained from buried paleosols of coastal dune ridges in Veracruz with the aim to reconstruct the environmental conditions during their formation as well as the phases of stability (pedogenesis) and instability (sedimentation) of the landscape. Three profiles were studied in the areas of Punta Delgada, PD (in the north), Palma Sola, PS, and La Mancha, LM (in the south). The chronological frame was constructed by radiocarbon dating of paleosols organic matter and pedogenic carbonates, and by Optical Stimulated Luminiscence (OSL) dating for the dune sediments. For each section several paleosols levels were identified whose properties permitted the differentiation of pedogenetic trends as well as their periods of formation. Nevertheless, the three sections did not provide for a continuous record of pedogenesis and sedimentation, as most of the paleosols are truncated by erosion. PS is the most complete profile which is formed from Marine Isotope Stage (MIS) 5c to MIS 1, with especially well-developed Holocene paleosols. LM includes only paleosols developed during MIS 4 and MIS 3, and PD shows only one paleosol originated during MIS 2. Although, the chronology is not complete as it has been constructed with a few dates, we consider each section contains information from different chronological windows. The results demonstrate that the oldest paleosols formed under more humid conditions during MIS 5c to 5a and probably MIS 4. As the MIS 4 to MIS 2 paleosols contain pedogenic carbonates, we interpret drier climates or with higher evapotranspiration rates. Paleosols from the early Holocene exhibit vertic properties probably formed by seasonal climates. Soils from the Middle-Late Holocene are less developed, due to the activation of the dune sedimentation. The results found here are compared at a regional scale with the dune system in the northern Gulf of Mexico and Yucatan peninsula, revealing both synchronous and asynchronous systems of eolian dynamics. The major asynchrony relates to the Wisconsinian stage (MIS 4 to MIS 2) for which high intensity of dune development is documented in the Veracruz and northern coasts whereas no dunes of that age are found in the Yucatan peninsula.

Pedogenic carbonates are considered important indicators of past climatic changes. Their formation is due to calcite accumulation through evaporation processes in arid or semi-arid regions. Over time, secondary carbonate accumulation results in the development of calcic and petrocalcic horizons in soil profiles. In this study, we conducted an analysis of pedogenic carbonates as records of paleoenvironmental characteristics in the Teotihuacan Valley, Basin of Mexico. Micromorphological, mineralogical, and geochemical characteristics of secondary carbonates from three paleosol profiles (Cerro Gordo 1, Cerro Gordo 2, and Maseca 1) were analyzed. Pedogenic carbonates were characterized by irregular and variable carbonate crystal sizes, inclusions of soil particles, and dark or light micrite and microsparite laminations. Micromorphology and scanning electron microscopy revealed weathered plagioclase minerals as a potential source of calcium for carbonate precipitation. The 87Sr/86Sr ratio of carbonate laminar crusts and nodules from the analyses pedons in the study area also indicated that rocks of the Transmexican Volcanic Belt were the principal source of Ca and Sr for carbonates, while contribution of a far-distance eolian input was minimal. The δ13C isotopic composition evidenced a mixture of C3 and C4 plants during the Pleistocene and a transition to a higher proportion of C4 vegetal cover during the Holocene. This agreed with an increase in modeled paleo-temperature from 10.9 °C to 13.7 °C based on 18O-temperature equations. Our results support those determined for the regional paleoenvironment during the Pleistocene, the Pleistocene-Holocene transition and Mid-Late Holocene.

Paleosols interbedded with pyroclastic deposits have been proven to be an important paleoenvironmental proxy for the late Quaternary in Central Mexico. We studied a key upland section and several profiles on the slopes and lowlands of the Tlaxcala Block, assuming that the topographic variability of the soil-sedimentary mantle contains the complete record of the landscape history. The upland section included three paleosols separated by tepetates (compact volcanic pedosediments) and reflected a general trend of environmental evolution during the last 40 ka. Particle-size distribution, bulk chemical composition, magnetic characteristics, computed tomography, and micromorphological observations demonstrated a strong seasonality of paleoclimate at the end of MIS3, followed by cool wet conditions during the last glacial maximum, subsequent warming at the beginning of the Holocene, and drying during the last 3 ka. It was shown that tepetates had well-developed pedogenetic features that contribute to the paleosol record. The studied slope and lowland profiles reflected the main phases of geomorphic activity in the terminal Pleistocene and the early Holocene. These phases are linked to paleoclimate fluctuations in Central Mexico at the end of the last glaciation.

The martian surface has been continuously exposed to galactic cosmic radiation. Since organic compounds are degraded by ionizing radiation, knowledge of their decay constants is fundamental to pred...

Rock surfaces covered with desert varnish frequently feature petroglyphs and thus comprise an important resource for the artistic expression of ancient societies. Knowledge about the processes of varnish formation would be helpful to assess the production, regeneration and durability of this “natural canvas” and related rock art. We performed a multidisciplinary study of rock varnish associated with petroglyphs at the archaeological site of La Proveedora (Sonora, Mexico) that has been occupied by humans for at least 4500 years. An inventory and mapping of these ancient engravings revealed 5873 individual images on 1331 rock surfaces. Classification of these motifs showed that geometric forms were the most commonly featured, followed by zoomorphic and anthropomorphic designs. Colorimetric measurements according to the L*a*b* system confirmed that the carvings have a strong color contrast with the background patina. Petrographic observations revealed the variable thickness of the varnish coating, which penetrates deeper into the granitic rock at contacts with plagioclases and ferromagnesian minerals, forming a “rooted” configuration of the lower boundary. Under SEM thin globular laminae were observed; plagioclase and biotite adjacent to the varnish showed signs of alteration. EDS microanalysis, LIBS and X-ray diffraction demonstrated that the patina consists of Fe and Mn oxihydroxides and clay minerals with differing amounts of Fe and Mn within the coating. These results support the polygenetic model of rock varnish development. Weathering of granite and eolian particles give rise to clay mineral formation, whereas Fe and Mn mobilization and reprecipitation is controlled by microorganisms. Varnish formation was more intensive under moister conditions which prevailed in Sonora during the terminal Pleistocene. Thus, rock varnish comprised a non-renewable resource for ancient artists, being a relict feature. The Holocene rates of patina development were too slow to re-pigment engravings, so the petroglyphs represent a persistent element of a cultural landscape. We attribute the surprising durability of the dark coatings to the “rooted” configuration of their lower boundaries that could be important for petroglyph preservation.

The history of the development of landscapes and land-use systems on the northern border of the forest-steppe zone of Russia (basin of the Tuskar River, Kursk region) is reconstructed. A multidisciplinary approach includes geomorphological, lithological, paleopedological, micromorphological, radiocarbon, paleobotanical (spore-pollen, carpological, pedoanthrocological) analyzes in the study of soil-sedimentation archives of floodplains (Shumskaya section), slopes (Pereverzevo section), and ravines (Senovaya gully section). The sequences of sediments and soils within accumulative and trans-accumulative archives are one of the most complete and reliable sources of information not only about climate changes, the evolution of ecosystems in the Holocene but also about the history of land use.The formation of a floodplain and a new ravine-gully network in the Late Ice Age backfilled the geomorphological basis for Holocene landscapes. Alluvium, proluvium, and colluvium partially filled the Late Pleistocene floodplain and ravine. In the early Holocene, with limited sedimentation, a well-developed soil, Luviс Gleyic Phaeozem, formed on the stable surface of the newly formed landforms. Its 14C-age is 8.1-8.7 ka yrs cal BP. This paleosol is widespread not only in the forest-steppe area of the Russian Plain but throughout the world. At the beginning of the middle Holocene, during droughts, as a result of strong fires and increased erosion, this paleosol in the floodplains and bottoms of ravines was buried by alluvium and colluvium. An episode of afforestation of the area is also noted. The slopes were covered with deciduous forests with oak and linden. This led to the formation of Gleyic Cutanic Luvisol (Humic, Siltic), as evidenced by the humus-clay cutans in the Ah horizon and degradation of Phaeozem. Strong fires during droughts periodically resumed and were accompanied by a subsequent catastrophic increase in runoff and accumulation of colluvium in the bottoms of ravines. They happened around 8.1, 7.4, and 5.2 ka yrs cal BP, as evidenced by the finds of oak coals, and ferruginous-manganese nodules with a carbonaceous core in colluvial loams. The oak was preserved on the slopes, while other parts of the catchment were essentially treeless. In the late Holocene, the afforestation process intensified. However, about 2.8-2.5 ka years ago, arable farming began to spread in the studied area. In the immediate vicinity of the study site, there were settlements and numerous villages of the Scythian culture population. Deforestation and plowing of land with wooden ralo (ancient Slavic plow) caused slight soil erosion and accumulation of agro-colluvium in the bottoms of the ravines and on the floodplain. With the appearance of iron parts on wooden ralo, the plowing depth increased. Due to the increase of population since the beginning of the new era (4-5 centuries AD), the catchments were cleared for arable land. The onset of continuous erosion and intensive redeposition of the soil mass containing pollen of weeds and cultivated cereals correlates chronologically with the expansion of the population of the Chernyakhov culture into this region. Since that time, the agricultural use of the catchment area and anthropogenic deforestation has continued. The study was supported by the RFBR, project N19-29-05024mk.

Los Necrosoles son suelos relacionados con entierros cuyas propiedades resultan de las condiciones particulares del entorno de la inhumación. Su caracterización por medio de técnicas de geociencia forense, puede aportar herramientas que maximicen la efectividad de la búsqueda de entierros clandestinos, situación relevante en Latinoamérica. El objetivo de este estudio fue identificar rasgos y procesos pedo-antropogénicos que caracterizan a los Necrosoles, específicamente, se identificaron diferencias micromorfológicas y químicas. Se estudiaron tres perfiles de suelo de cementerios rurales en el cañón del río Cauca, en Colombia, y dos perfiles de la misma zona, fuera de la influencia de los cementerios. La comparación de ambos, perfil dentro vs perfil fuera del cementerio, permitió determinar las variaciones en las propiedades producto del impacto de los entierros. Las muestras de los suelos fueron caracterizadas químicamente y mediante métodos micromorfológicos. Los resultados demuestran que las variaciones entre los suelos de cementerios, respecto a sus referentes naturales, son la presencia de microfragmentos de madera de ataúd y de hueso, minerales con orientaciones paralelas, concentración alta de raíces finas al nivel del entierro y mezclas de agregados pedogénicos entre una matriz no pedogénica. Desde el punto de vista químico, las variaciones observadas fueron la mayor concentración de S, Fe móvil, P, además del incremento en la capacidad de intercambio catiónico del suelo. El presente estudio demostró la utilidad de la micromorfología de tres suelos como herramienta en la confirmación de la presencia de Necrosoles a partir de métodos usados en la arqueología y geociencia forense. Se proponen rasgos diagnósticos modelo para la identificación de entierros clandestinos, en particular para zonas que reúnan condiciones de contextos pedológico, geomorfológico y bioclimático similares y que serán útiles en la geociencia forense. Estos cambios de organización a nivel de microestructura en Necrosoles, se presentaron de forma escaza, localizada y heterogénea, pero no fragmentados ni dispersos, lo que pudo ser posible por la disposición espacial del entierro en el suelo y a que los restos esqueléticos bien conservados que fueron exhumados cuidadosamente. En este sentido los Necrosoles se diferencian de otros suelos antropogénicos como los Tecnosoles, Urbanozems y suelos arqueológicos, donde los microartefacos son abundantes.

A method of the Holocene paleoenvironment reconstruction based on the analysis of pedobiomarkers in tell deposits is suggested. On the Yunacite tell, such a reconstruction has been accomplished applying two types of environmental records: (a) soil records documented in the profiles of two soils within the middle and lower parts of the tell and reflecting changes in the conditions of pedogenesis averaged over relatively long periods and (b) soil-sedimentary records in the cultural deposits of the Eneolithic and the Early Bronze Ages (3.5 and 2.5 m in thickness, respectively). The lower soil identified at the depth of 9.2–10.0 m was buried about 5000 cal BC (the chronology is based on calibrated 14C dates). The low humus and high carbonate contents indicate arid climate conditions in the 6th millennium BC. The middle soil at a depth of 5 m was formed for about 1500 years (4350–2850 cal BC) according to 14C data. According to chemical and micromorphological analyses, it has a higher humus content and is more leached of CaCO3, as it was formed under more humid climate conditions. A detailed time record of CaCO3 leaching processes has been revealed in the sediments of the Eneolithic and the Bronze ages that were accumulating for about 600 years in the 5th millennium BC and for about 350 years in the 3rd millennium BC. Due to the increase in climate humidity, the leaching process was intensified twice: about 4500 and 2800 cal BC. In the same two periods, especially in the former period, the proportion of residues of hydrophilic beech increases significantly, and the proportion of oak residues decreases. Similar data have been obtained by the analysis of phytoliths and pollen.

En este trabajo se presenta un análisis integral del registro sedimentario y paleopedológico en una secuencia edafo-sedimentaria encontrada en la terraza baja del arroyo Tinajas, estado de Sonora. El objetivo de esta investigación es establecer los mecanismos de formación de dicha secuencia que permitan hacer una reconstrucción de las condiciones paleoambientales. La secuencia consiste de un suelo moderno y once paleosuelos intercalados con sedimentos fluviales. Se determinaron sus propiedades físicas (color, granulometría), químicas (pH, conductividad eléctrica, contenido de calcio total), de magnetismo de rocas y micromorfológicas. Así mismo, se hizo la identificación de la mineralogía de arcilla por difracción de rayos X. Prácticamente todos los paleosuelos están decapitados. Debido a la falta de horizontes A, el marco cronológico de la secuencia se obtuvo usando una pequeña cantidad de materia orgánica encontrada en el paleosuelo 8. Para concentrar la materia orgánica, se hizo una extracción por desmineralización con ácido fluorhídrico. Esta materia orgánica desmineralizada se dató por 14C por la técnica de AMS (Accelerator Mass Spectrometry), arrojando una edad de 8415 ± 39 años cal AP (Beta 473502). Los resultados muestran que los paleosuelos tienen un bajo grado de desarrollo. A pesar de ello, es posible establecer las principales tendencias pedogenéticas: la parte baja de la secuencia muestra paleosuelos de granulometría fina, con fuertes rasgos reductomórficos y propiedades vérticas. En contraste, los paleosuelos superiores son de textura más gruesa, con mayor porosidad biogénica e, inclusive, con revestimientos arcillosos. A partir del paleosuelo 7, se aprecia un cambio en la energía del relieve, dado por variaciones sedimentológicas (gradación inversa, aumento del tamaño de grano del sedimento), el cual es más evidente en los paleosuelos 2, 3 y 4, dada la alta concentración de gravas, mal seleccionadas y angulosas, que se asocian con procesos fluvio-coluviales. Suponemos que este cambio en el tipo de pedogénesis, sumado a las variaciones sedimentológicas, es debido a oscilaciones climáticas ocurridas en el Holoceno medio a nivel regional, ya que no se tiene documentada actividad tectónica reciente que pudiera influir.

The main purpose of this work was to study and understand the interaction that occurred between an acid solution spilled from Buenavista del Cobre Mine and the soils located in the Bacanuchi River area. The question put forward in this work was: if the soils of the area were able to cushion the impact of the acid solution?. Two soil profiles were examined: Profile 8A, was located on the riverbank and was affected by the spill, whilst Profile 8B, located on the first terrace of the river valley, remained intact . Both soils profiles were chemically characterized. An additional three surface samples (0-30 cm) were taken for geoavailability tests (RBI, SB2, belonging to Profile 8B, and SB3, belonging to Profile 8A). Two further samples, representing typical unaltered soils of profiles 8A and 8B, were taken for their micromorphological study. The results showed a difference between the two profiles, with profile 8A having more acidic pH, greater electrical conductivity, and higher concentrations of Fe, Pb, Cu and As than profile 8B. The geoavailability test showed that the elements enriched in SB3 were stable and not available to the aqueous phase. The soils of Bacanuchi River contain carbonates, which interacted with the acid solution and stabilized the potentially toxic elements presents in the spilled acid solution. This interaction with carbonates promoted a new minerals formation such as gypsum and copiapite. So, the release of contaminants from soil to surface and ground waters is improbable, unless the redox conditions change or a new spill occurs releasing the potentially toxic elements (PTE) to the environment. In this work we show the importance of pedogenic carbonates in soils of arid and semi-arid environments; these carbonates represent a natural geochemical barrier, that can prevent the migration of PTEs in mining areas.

Este artículo muestra las aproximaciones interdisciplinarias que integran conocimientos respecto a los suelos de cementerios contemporáneos y antiguos e inhumaciones clandestinas que producen interés científico bio-geo-arqueológico, forense reciente, lo anterior es lo que compila el estudio de los Necrosoles. Las investigaciones al respecto, plantean interrogantes pedogenéticos, antropogénicos, morfológicos, de características físico-químicas y microbiológicas. Así los Necrosoles se definen con precisión e incluyen en propuestas para sistemas taxonómicos locales y mundiales. Los suelos de los cementerios tienen propiedades físico-químicas y microbiológicas variables, antrópicas, temporalidades e insumos orgánicos e inorgánicos exógenos y predominancia de procesos de cambio ambiental. Actualmente, las necrópolis en las urbes y la proximidad a fuentes de agua e impactos de estos suelos en la salud pública y ambiente, se evalúan en investigaciones científicas. También aumenta el interés por las características de entierros ilegales de cuerpos humanos e integración de herramientas pedológicas y forenses. Revisamos los estudios de Necrosoles y el desarrollo de la investigación científica experimental ligada a efectos e implicaciones de entierros humanos

International audience; Catastrophic events (climatic, tectonic, volcanic, etc.) frequently cause geomorphological instability, which interrupts normal pedogenesis and switches the processes of surface erosion and/or sedimentation. These processes have an effect on the distribution of ancient settlements and can be the cause of the abandonment of cities. In the Lerma Valley, particularly in the Tres Mezquites area, surveys and extensive excavations have been conducted to estimate the nature and density of pre-Hispanic settlements on the alluvial plain and in the piedmonts. Most of the archaeological structures are covered by dark clayey soils (Vertisols). This includes the PA3_El Pitayo site, where an accumulation of black earth has been detected on the floors and walls of a collapsed building. We have studied in detail the Vertisols and the black earth around the site to establish to what extent this dark earth is an in situ product of the soil-forming factors, or if its accumulation is due to erosion/sedimentation processes, which could affect the occupation of the site, or the result of anthropic activity for leveling. The Vertisols and the dark earth are characterized by different means (physical, chemical, micromorphology, clay mineralogy, and radiocarbon dating). The results show that both the Vertisols and the black earth are very clayey, with angular blocky structures and slickensides (properties that are typical of vertic soils), and smectite as the main clay mineral. Besides smectite, under the microscope, a high amount of fresh volcanic glass is identified, suggesting that volcanism could be responsible for the abandonment of the study site. However, there are no known volcanic events related to the age of abandonment. As a consequence, we consider that landslides triggered by seismic activity/climatic events impacted the settlement.

Key evidence of human occupation in Africa during the Middle Palaeolithic (Middle Stone Age [MSA]) is available from the south and east of the continent, where semi-arid climate prevails. Rare evidence of MSA human occupation in the humid tropical region was recently reported from Equatorial Guinea. To identify if paleolithic human occupation occurred in the tropical forest, the stratigraphy of the recently discovered archaeological site “Mabewele I” was analyzed using a paleopedological approach. The properties evaluated along a vertical profile are: granulometry, magnetic susceptibility (K), free iron extractable with sodium dithionite (Fed), total organic carbon (TOC), chemical composition by X-ray fluorescence (XRF), X-ray diffraction mineralogy (XRD), ternary plot of the three main oxides (SiO2-Al2O3-Fe2O3), phytoliths and micromorphology. The predominant fraction is sand, with a significant clay content (> 30 %). The K and the Fed presented low values, as well as the TOC. XRF showed few variations along the sequence and XRD showed that the clays are mainly kaolinites, with a very low component of vermiculites. The phytoliths correspond to tropical vegetation with few changes in the vegetal composition between the deep and superficial zones. A charcoal from the lower part of the profile was dated between 12.57-12.24 ka cal BP, while the main artifact horizon was located at the bottom. The analytical results appear contradictory: on the one hand, there is evidence of intense chemical weathering under a humid tropical climate, but the clay cutans in the pores are very scarce and incipient and the iron nodules are mostly anorthic. This indicates that the sequence is composed of pedosediments associated with a high environmental dynamism, with short periods of erosion-sedimentation-pedogenesis. The results allow us to propose that humans inhabited the tropical forest during the MSA and that erosion-sedimentation processes could be related to anthropization processes.

Rock varnish is a thin layer (1-40 microns every 1000 years), dark-reddish in color (30% Mn and Fe oxides, 70% clay minerals), that coats a rock surfaces in the northern Mexican deserts. This accretion has been used as a canvas by ancestral human groups to record different types of motifs (zoomorphic, geometric and anthropomorphic) in the northern Mexican desert (Sonora and Chihuahua). These petroglyphs reflect the cultural and artistic nature of past inhabitants and the varnish preserves them through the millennia. Rock varnish coats a variety of rock types, and this paper explores differences in the chemical composition and interaction of varnish and the underlying rock. We studied varnish from three different sites: Samalayuca (Chihuahua); El Álamo (Sonora); and La Proveedora (Sonora). The analytical techniques of microscopy, X-Ray Diffraction (XRD) and Laser Breakdown Spectra (LIBS), reveals a similar chemical composition (Mn, Fe, Ca and Al mainly) that it does not depend on the lithodiversity or location (Samalayuca -sandstone-, El Álamo -sandstone- and La Proveedora -granite-). We observed differences in the contact between the varnish and the underlying rock. Varnish penetrate into decayed minerals such as plagioclase; thick accumulations can occur on hard minerals such as quartz. Like prior research, we find little important contribution of material from the underlying to its varnish coating and conclude its main component derives mostly from aeolian deposition.

espanolLas actividades realizadas por las sociedades agricolas prehispanicas poco complejas, no son usualmente consideradas como factores importantes de degradacion del suelo. Sin embargo, la repeticion de actividades cotidianas durante cientos de anos puede afectar sustancialmente sus caracteristicas. En el sitio de La Playa, las modificaciones del paisaje producidas por las actividades cotidianas, tales como la construccion de hornos de tierra para cocer alimentos, campos de maiz con un complejo sistema de canales de riego, y la practica de rituales mortuorios (crematorios, cremaciones e inhumaciones), juegan un papel importante en las transformaciones de los rasgos naturales del suelo. En este articulo se muestran las caracteristicas de los paleosuelos de La Playa, que constituyeron la superficie de ocupacion durante el Periodo de Agricultura Temprana (4500-1800 cal AP), y la influencia que las actividades de subsistencia diaria tuvieron en su configuracion. Para ello, se muestran los resultados obtenidos en campo y en laboratorio de tres perfiles de secuencias pedosedimentarias formadas durante el Holoceno tardio en La Playa, Sonora (NW de Mexico). Las caracteristicas evaluadas son: estructuracion, diferenciacion de horizontes, textura (a tacto y por separacion de fracciones), color, porosidad, pedregosidad, propiedades magneticas, contenido de carbono organico, carbonatacion, presencia de cutanes, nodulos y/o concreciones, entre otros rasgos pedologicos. Estudios previos muestran que los Fluvisoles de La Playa estan pobremente desarrollados y se formaron a partir de depositos aluviales (compuestos en gran medida por suelos redepositados). Las propiedades fisicas y quimicas indican periodos cortos de pedogenesis superpuestos, desarrollados bajo un clima arido durante los ultimos 4000 anos. Las caracteristicas de todos los perfiles son muy similares, indicando las mismas condiciones pedogeneticas; mientras que las propiedades micromorfologicas y magneticas muestran claramente que el suelo esta profundamente perturbado por las actividades humanas, principalmente quema en los hornos y cremaciones. EnglishThe activities carried out by preindustrial agricultural societies are not usually considered as important factors of soil degradation. Nonetheless, repetitive human daily activities for hundreds of years can substantially transform the natural properties of the soils. At the site of La Playa, Mexico, the activities of early farmers modified the landscape and had an important role in the physical transformations of the natural soil features. This paper depicts the characteristics of La Playa paleosols, which were the living surface of the Early Agriculture Period community (4000 - 1800 cal BP) and we discuss the influence of daily subsistence activities on the soil. The soil features (structuring, differentiation of horizons, texture-in field and laboratory, color, porosity, stoniness, magnetic properties, organic carbon content, carbonation, presence of cutans, nodules and/or concretions, among other pedological features) of three profiles with pedosediments (paleosols interbedded with sediments) formed during late Holocene are discussed. Our study suggests that La Playa Fluvisols are poorly developed and were formed with alluvial deposits (largely composed of reworked soils). The pedogenic properties indicate that overlapping developed during short time periods of stability, under arid conditions of the last 4000 years. The uniformity of the features in all the studied profiles indicate similar pedogenetic conditions across the site. The micromorphological and magnetic properties clearly show that the soil was deeply disturbed by human activities, mainly by roasting features to process food, crematories and grave digging to bury the dead, and removing soil for several agricultural activities.

Environmental conditions and human-landscape interaction during the onset of the irrigated agriculture in Oasisamerica are not clear yet. In la Playa site (Sonora, NW Mexico), the evidences of sedentary population, land cultivation, and water management developed after the end of Altithermal period (around 4500 yr BP) include more than 550 archaeological features including hundreds of human cremations and a net of buried artificial channels. These findings were closely associated with several palaeosol levels alternating with sediments within a large alluvial fan. We studied micromorphological features, physical characteristics (color, texture, rock magnetic properties), and composition of organic matter, from three profiles (Maravillas, Zanja, and Cuatro Suelos), to reconstruct pedogenesis and sedimentary environment of the palaeosol sequences. Additional paleoenvironmental information was extracted from pollen assemblages, extracted from the Cuatro Suelos profile. The results pointed to a long period of geomorphic and climatic stability in the early-middle Holocene marked by a well-developed red Cambisol. This period was followed by an unstable interval around 4.5 kyr BP marked by severe erosion of earlier soil profiles and sedimentation of different kind: channel, floodplain, and fluvio-eolian. Later synsedimentary Fluvisols were formed showing signs of predominantly arid pedogenesis, interrupted by occasional flooding; indicators of human impact were also encountered. We conclude that the shift to irrigated agriculture as the main subsistence activity occurred during the period of major climatic and geomorphic fluctuation and then irrigation developed further under dry environment with limited water resources during the Late Holocene.

Complex geoarchaeological research of the archaeological sites with continuous long-term occupation could provide insight into environmental change and human-landscape interaction during the transition from hunter-gatherer to horticulture economy in the north-west of South America. We performed a paleopedological study in the new sections at Tequendama (rockshelter site) and Aguazuque (open-air site) two key pre-ceramic sites of the Savannah of Bogota region of Colombia, combined with traditional archaeological and paleontological investigations. The chronological scales of the sections based on a large number of 14C dates show that their occupation periods are complementary and together cover the period from the terminal Pleistocene to late Holocene. The material of the archaeological layers has a colluvial origin with large tephra input. Presence of volcanic components influence pedogenesis supporting development of granular structure, dark humus accumulation, and Andic properties that could not be used for paleoenvironmental reconstruction. Micromorphological observations however show abundant evidence of pedogenic carbonate accumulation that we interpret as evidence of gradual aridization during the middle Holocene. This conclusion is supported by the paleontological data, an upward increase of the frequency of Cavia sp. remains, and agrees with the regional palynological proxies. Aridization was the background environmental trend during the transition period from a hunter-gatherer economy to an early horticulture and plant and animal domestication.

Fragipan is a compacted but non-cemented subsurface horizon, considered as a pedogenic horizon, but the mechanism of its formation is not well understood. The main hydro-consolidation hypothesis involves a collapse of soil structure when it is loaded and wet, resulting a reorganisation of pore space. Soils with fragipan never have been marked in Russian soil maps. In the South Karelia, located in Eastern Fennoscandia (34.50921 E and 61.33186 N, 110 m asl) we studied a soil profile of Albic Fragic Retisol (Cutanic), developed in the glacial till of Last Glaciation with flat subhorizontal topography under an aspen-spruce forest. The aim of this study was to demonstrate how the fragic horizon was formed in the Retisol located in South Karelia. Observations were made in each soil horizon using micromorphological method, particle size analysis and the study of mineralogical composition of clay fraction by X-ray diffraction. The analysis of the morphological description combined with the laboratory data have led us to the conclusion that the consolidation of the fragipan occurred after the textural differentiation of the profile, following the Atlantic Optimum, and does not depend on the presence of swelling clay minerals. The well-developed argic horizon was probably formed around 6000 years ago, under climatic conditions more favourable for clay illuviation than in present time. Fragipan is supposed to be developed during the Sub-Boreal cooling.

espanolLos suelos de los oasis antarcticos, en las areas libres de hielo tanto en la costa como tierra adentro rodeadas por los glaciares terrestres o plataformas de hielo, atraen la atencion como uno de los componentes de los ecosistemas mas extremos de la Tierra. El conocimiento sobre las etapas iniciales de edafogenesis, formacion y estabilizacion del solum, interaccion entre los componentes organicos y minerales en estos suelos es todavia limitado. Hemos realizado un estudio micromorfologico de algunos perfiles de suelos superficiales, desarrollados en los sedimentos recientes no consolidados, bajo musgos y liquenes en el Oasis Schirmacher. El material mineral esta dominado por particulas de arena, de minerales primarios (cuarzo, feldespatos K-Na y micas). Los granos de cuarzo demuestran estructuras superficiales indicativas de la fragmentacion criogenica, mientras que la biotita tiene signos de alteracion quimica: intemperizacion a lo largo del clivaje, deformacion de las laminillas, perdida de los colores de interferencia y del pleocroismo. A pesar de las condiciones ambientales severas, el intemperismo incipiente genera minerales arcillosos y oxidos de hierro que se incorporan al material fino. Este ultimo forma recubrimientos discontinuos sobre los granos gruesos generando un modelo de distribucion c/f quitonico. La distribucion de los componentes finos en forma de recubrimientos sobre los granos gruesos proporciona una interaccion maxima con la humedad del suelo y la materia organica y con la generacion de micro-habitats para microorganismos. La caracteristica micromorfologica comun de los suelos estudiados consiste en una matriz compleja que combina tejidos bien conservados de musgos y liquenes y particulas minerales distribuidas entre ellos. Se concluye que los cuerpos edaficos estudiados son sin-sedimentarios: el deposito del material mineral ocurre simultaneamente con el crecimiento de las plantas primitivas. Los granos minerales estan atrapados entre los tejidos vegetales que forman el “armazon” de la matriz del suelo. Esta interaccion permite tambien la conservacion de la materia organica en la cubierta del suelo. Los suelos estudiados demuestran similitudes a las costras biologicas de otros ambientes terrestres extremos del presente y del pasado. EnglishThe soils of Antarctic oases - coastal as well as inland ice-free areas limited by ice sheet or ice shelves attract attention as a block of one of the most extreme terrestrial ecosystems of the Earth. The knowledge about early stages of pedogenesis, solum formation and stabilization, interaction between organic and mineral components in these soils is still limited. We performed micromorphological investigation of several thin soil profiles developed under mosses and lichens on the sediments deposited by meltwater in a lake depression of Schirmacher Oasis. Mineral components are dominated by sand particles of primary minerals (mostly quartz, K-Na feldspars and micas) derived from gneiss bedrock. Quartz grains exhibit surface structures indicative of cryogenic fragmentation, whereas biotite has signs of chemical alteration: exfoliation along cleavage planes, deformation of laminae, loss of interference colours and pleochroism. Despite severe environmental conditions, incipient weathering occurs that contribute clay minerals and iron oxides to the fine material. The latter forms discontinuous coatings on the coarse grains providing a chitonic c/f related distribution pattern. Arrangement of the fine components in form of coatings on coarse grains provides their maximal interaction with soil moisture and organic matter and generation of microhabitats for the microorganisms. Common micromorphological features of the studied soils is a complex groundmass which combines well preserved organic tissues of mosses and lichens and mineral particles spread among them. We conclude that the studied soil bodies are synsedimentary: fluvial (and possibly eolian) deposition of mineral material that occurs simultaneously with the growth of primitive plants. The mineral grains are trapped between plant tissues which form a framework of the soil matrix. This interlacing provides also conservation of organic material within the soil layer. Studied soils demonstrate similarities with the biological crusts of other present and past extreme terrestrial environments.

espanolLa region de Yalahau al norte de Quintana Roo, Mexico, contiene abundantes humedales de agua dulce y una historia de ocupacion Maya que abarca casi 3000 anos. Los mayores niveles de poblacion regional ocurrieron durante el periodo Preclasico tardio, del 100 AC al 350/450 DC. Los Mayas construyeron alineamientos rocosos cruzando los pantanos, y se ha hipotetizado que estas caracteristicas funcionaron para atrapar suelos y agua para la produccion de alimento y para el uso de recursos biologicos como el perifiton. Los estudios paleoambientales de un humedal de la porcion oriental de la region sugieren que la ocupacion de la region de Yalahau y la manipulacion de los humedales, corresponden con un periodo cuando el manto freatico fue menor que en tiempos modernos, creando ecosistemas de humedal que eran mas productivos para el cultivo. Este trabajo presenta resultados que aplican este modelo a escala regional (en humedales en otras partes de la region). Treinta pequenos nucleos de suelo fueron colectados de 12 humedales a lo largo de la region. Para este Proyecto, 5 nucleos de 4 humedales fueron seleccionados para los analisis que incluyen micromorfologia y fechamiento por radiocarbono. Las laminas delgadas, estudiadas bajo el microscopio petrografico, fueron usadas para identificar los varios tipos de caracteristicas presentes en los nucleos, incluyendo carbonatos, materia organica, conchas, pirita, yeso y espacio poroso. En cada nucleo, distinguimos una unidad superior dominada por carbonato micritico biogenico y una unidad inferior caracterizada por una variedad de caracteristicas de suelo unicas, como cristales espariticos de calcita, pirita, yeso y propiedades gleycas. Basado en esto, se sugiere que mientras que los procesos formadores del suelo moderno son claramente uniformes a lo largo de la region y controlados por la inundacion anual regular (~7 meses de >1 m de profundidad de inundacion cada ano), en el pasado (periodo Preclasico), la inundacion era menos regular y los ambientes de humedal fueron mas pantanosos y variados. Ademas, se sugiere que las depresiones del Preclasico encontradas por los Mayas, fueron un recurso agricola de calidad que permitio el florecimiento de la region durante el Preclasico tardio. Sin embargo, como la inundacion se volvio mas regular al final del periodo Preclasico, la region fue abandonada, solo para ser re-ocupada en el Postclasico tardio, cuando los humedales fueron explotados para recursos acuaticos, mas que para la agricultura. EnglishThe Yalahau region of northern Quintana Roo, Mexico, contains abundant freshwater wetlands and a history of Maya occupation that spans nearly 3000 years. The highest regional population levels occurred during the Late Preclassic period, from ca. 100 BC to AD 350/450. The Maya constructed rock alignments crossing wetland swales, and these have been hypothesized as features used to trap soil and water for production of food and useful biological resources such as periphyton. Paleoenvironmental studies from a wetland in the eastern part of the region suggested that occupation of the Yalahau region, and manipulation of the wetlands, corresponded to a period when the water table was lower than in modern times, creating wetland ecosystems that were most productive for cultivation. This paper presents results that apply this model at the regional scale (in wetlands in other parts of the region). Thirty short soil cores were collected from 12 wetlands across the region. For this project, 5 cores from 4 wetlands were selected for analyses including micromorphology and radiocarbon dating. Thin sections studied under petrographic microscope were used to identify the various types of features present in the core sequences including carbonates, organic matter, shell, pyrite, gypsum, and pore space. In each core, it was possible to distinguish an upper unit dominated by biogenic-micritic carbonate and a lower unit characterized by a variety of unique soil features such as sparitic calcite crystals, pyrite, gypsum, and gleyic properties. Based on this, it is suggested that while modern soil forming processes are fairly uniform across the region and controlled by regular annual flooding (~7 months of >1m deep flooding each year), in the past (Preclassic period), flooding was less regular and wetland environments were more swampy and varied. Furthermore, it is suggested that the Preclassic depressions encountered by the Maya were a prime agricultural resource that allowed the region to flourish during the Late Preclassic period. However, as flooding became more regular at the end of the Preclassic period, the region was abandoned, only to be reoccupied in the Late Postclassic when wetlands were exploited for aquatic resources rather than for agriculture.

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.

A detailed pedocryostratigraphic scheme of the Late Pleistocene periglacial region of the East European Plain has been developed on the basis of study of the paleorelief, sediments, paleosols, and cryogenic horizons. OSL and 14C-dating of paleosols and sediments in Aleksandrov quarry and in other sections made it possible to substantiate this scheme and correlate it with analogous ones for different regions of Europe. The loess-paleosol sequence in Aleksandrov quarry (51º05'N, 36º08'E) does not have an analogous with respect to the completeness in the whole East European Plain. In the filling of paleobalka the Ryshkovo paleosol of the Mikulino interglacial (MIS 5e) is observed. Over this paleosol, the Valdai soil-sediment series (MIS 5d – MIS 2) is located. It includes four interstadial soils, two of them of the Early Valdai (Kukuevo and Streletsk ones), and two, sometimes three, of the Middle Valdai (Aleksandrov, Hydrouzel и Bryansk ones). The OSL date, 127 ± 8 ka BP, (beginning of MIS 5e) was obtained for a sample taken from the bottom of the Ryshkovo soil. The interglacial soil is overlain by the Seym layer formed mainly from destroyed and redeposited horizons of this soil. For the upper part of the Seym layer, OSL dates of 115 ± 7 ka BP and 112 ± 20 ka BP were obtained (MIS 5d). But the process of burial of Ryshkovo soil in the bottom of the paleobalka began at the end of the interglacial after a catastrophic forest fire. Large post-permafrost deformations - pseudomorphosis is confined to Selikhovodvor loess - MIS 4 (65 ± 8 ka BP). Two soils occurring between Seym and Selikhovodvor loesses: Kukuevo and Streletsk - Early Valdai (MIS 5c and MIS 5a). For Mlodat loess which separates those two soils (MIS 5b), OSL dates of 91 ± 1 and 89 ± 7 ka BP were obtained. For paleosols of Middle Valdai (MIS 3), 14C-dates were obtained: Aleksandrov (53.742 - 2.124 ka cal BP) and Bryansk soils (37.618 ± 0.668 ka cal BP). For Tuskar loess, which separates Alexandrov and Bryansk soils, OSL dates of 50 ± 3 and 51 ± 3 ka BP were obtained. The new stratigraphic scheme of Late Pleistocene agrees with the ideas of researchers from Eastern, Central, and Western Europe , which allows the following correlations. The identified paleosols correspond to the following intervals: Ryshkovo – Eemian interglacial (127-117 ka BP); Kukuevo to Amersfoort + Brørup – Saint-Germain 1 (105-95 ka BP); Streletsk – Odderade to Saint-Germain 2 (about 85-75 ka BP); Aleksandrov to Oerel (56-53 ka BP); Hydrouzel to Moershoofd – Poperinge (44-45 ka BP) and Hengelo (40-38 ka BP); and Bryansk (33-27 ka BP) to Stillfried B, Denekamp or Grand Bois interstadials. The reconstructed Late Pleistocene loess-paleosol sequence has the most similar structure with loess-paleosol sequences of Ukraine, with sequence Dolní Věstonice in Moravia (Czech Republik), Stillfried in Austria and Mainz-Weisenau in the Rhenish area (Germany), and other archives. This work was supported by RFBR, grant N19-29-05024 mk.

Maya blue is a well-known pre-Hispanic pigment, composed of palygorskite or sepiolite and indigo blue, which was used by various Mesoamerican cultures for centuries. There has been limited research about its continued use during the Viceroyalty period, therefore, the sixteenth century is the perfect period through which to study the continuity of pre-Hispanic traditions. The fact that the indigenous people were active participants in the construction and decoration of convents makes their wall paintings a good sampling material. X-ray fluorescence (XRF), scanning electron microscopy (SEM) and X-ray diffraction (XRD) were performed in samples of blue found in convents across Puebla, Tlaxcala and Morelos in order to identify whether the numerous hues of blue were achieved with Maya blue or with other pigments. We found no copper (Cu) or cobalt (Co) with the XRF, so several pigments, such as azurite, smalt or verdigris, were discarded. With SEM, we discovered that the micromorphology of certain blues was clearly needle-shaped, suggesting the presence of palygorskite or sepiolite. In addition, we found silicon (Si), magnesium (Mg) and aluminum (Al) by using energy-dispersive X-ray spectroscopy (EDS) in all blue samples, which also suggests the presence of these magnesium-rich clay minerals. With the XRD samples, we verified that the blues were produced with these two clay minerals, thus confirming that several wall paintings were manufactured with Maya blue. These findings confirm that this particular manmade pre-Hispanic pigment, Maya blue, was an important pigment prior to the Viceroyal period.

The martian surface has been continuously exposed to galactic cosmic radiation. Since organic compounds are degraded by ionizing radiation, knowledge of their decay constants is fundamental to predicting their stability on the martian surface. In this study, we report the radiolysis constant for the destruction of soil organic compounds at a starting concentration of ∼2011 μg C/g

In Cananea, Sonora (northwestern Mexico), occurred a spilling of 40 000 m³ of an acid solution coming from the Buenavista del Cobre mine, which reached some tributaries and the main water stream of the Sonora River basin. This study aims to evaluate magnetic properties as proxies to assess residual pollution in soils and sediments affected by this kind of events. Particularly, the study focused on the temperature dependence of magnetic susceptibility. Measurements of volume magnetic susceptibility vs temperatures were performed, heating samples to 700 ºC and cooling them back to room temperature. A strong increase (from three to six times the initial value) of magnetic susceptibility during heating was observed on precipitates of the acid solution dam, and on affected soils and sediments, starting at ~330 ºC, and reaching a maximum at ~430 ºC. An even stronger increase was observed during cooling. These increases are due to the transformation of iron bearing minerals (as jarosite, goethite and ferrihydrite) to ferrimagnetic iron oxides (as magnetite). Samples of non-affected soils and sediments did not exhibit this increase during heating, but a decrease at ~550 ºC related to (titano)magnetite Curie temperature, and they presented lower κ values during cooling. The transformation of these iron-bearing minerals (commonly occurring in mine wastes and acid drainage) marked by a strong κ increase during heating, can be used as an indicator of the presence of residual pollution.

"Una de las problemáticas ambientales principales de las zonas mineras es la generación del denominado drenaje ácido de mina (DAM), que tiene un impacto negativo para el ambiente y la salud humana debido a las altas concentraciones de elementos potencialmente tóxicos (EPT). Existen varios tratamientos que utilizan diferentes tipos de rocas para el control de drenaje ácido, entre las cuales la caliza es muy utilizada debido a su excelente potencial de neutralización. Otro material que reúne estas características es el carbonato de origen pedogénico; sin embargo, no hay estudios que valoren su utilidad. Se estudió la efectividad de un edafosedimento carbonatado y una caliza en el tratamiento del DAM de una mina abandonada. Se realizó una caracterización química, mineralógica, geoquímica y micromorfológica de los dos materiales formados de carbonatos de calcio con diferente origen (edafosedimento y caliza.). Se realizaron pruebas en lotes, utilizando edafosedimento carbonatado-DAM con relaciones 1:2.5 y 1:20 (sólidog: liquidomL), y caliza-DAM con las mismas relaciones. Se midió la cinética del pH y conductividad eléctrica a la primer hora y posteriormente cada 24 hs hasta las 259 hs. Los valores de pH finales en ambos experimentos cambiaron de ácidos a neutros. Por otro lado, la conductividad eléctrica bajó más en los tratamientos con caliza que en el edafosedimento sobre todo en la relación 1:2.5, lo que se atribuye a la presencia de sales. Adicionalmente, los resultados químicos en el DAM después del tratamiento indican una retención del 100% de Cu, Fe, Ni, Al y Cd en la caliza y en el edafosedimento una relación 1:2.5. En cuanto al Zn se logró una retención con valores por debajo de los límites máximos permisibles. Por el contrario, en todos los tratamientos se libera Mn de la fase sólida, y tiende hacia una mayor concentración en el tratamiento con caliza. El edafosedimento carbonatado resultó ser eficiente en la neutralización y precipitación de los EPT y más viable la relación 1:20, ya que la relación 1:2.5 presentó altas concentraciones de Na+ y Cl- que pueden ser problema de salinidad."

espanolLas ceramicas arqueologicas, al igual que otros tecnofosiles, son parte importante del registro de impacto humano prehispanico en el sur de Mexico y Centroamerica, proporcionando una medida en la cual podemos tratar de definir el Antropoceno temprano en el continente (ca. 3000 - 1000 A.P.). Este impacto se ve tambien reflejado en la utilizacion de las materias primas para la fabricacion de las pastas ceramicas. Se realizo una revision de los componentes microscopicos mas comunes de la ceramica Maya (de regiones de Campeche, Chiapas y Yucatan), utilizando el concepto de fabrica de la micromorfologia de suelos se evidencian rasgos heredados de suelos y sedimentos utilizados como materias primas. Se dio particular interes a: microestructura, masa basal, iluviacion de arcilla, rasgos redoximorficos, restos organicos, fases de intemperismo de componentes minerales y rasgos de alteracion por sepultamiento. Muchos de estos componentes han sido descritos antes, sin embargo, la atencion que se les ha dado en cuanto a la interpretacion de su origen y formacion en su contexto natural (previo a su conversion en ceramica) ha sido poca. La comprension de los procesos de formacion del suelo y sus evidencias microscopicas relictas en un artefacto, pueden ayudar para definir las fases de produccion ceramica, incluyendo el contexto de elaboracion de la pasta, coccion y etapas de abandono o desuso. Al mismo tiempo, estas evidencias microscopicas, reflejan la seleccion preferencial de cierto tipo de materiales. En conjunto, el aprovechamiento de dichos recursos es parte de una huella ecologica relacionada a cuestiones de sustentabilidad en la civilizacion Maya. EnglishArchaeological ceramics, like other technofossils, are such an important part of the record of pre-Hispanic human impacts in southern Mexico and Central America, that they provide a measure by which we can try to define the Early Anthropocene on the continent (ca. 3000 - 1000 B.P.). This impact is also reflected in the use of raw materials for the manufacture of ceramic pastes. A review of the most common microscopic components of Maya ceramics (from Campeche, Chiapas, and Yucatan regions) was carried out, using the soil micromorphology fabric concept, which showed traits inherited from soils and sediments used as raw materials. Particular interest was given to: microstructure, groundmass, clay illuviation, redoximorphic features, organic remains, mineral weathering stages, and alteration features by burial context. Several of these components have been described before; however, the attention given to the interpretation of their origin and formation in natural context (prior to conversion into pottery) has been limited. The understanding of soil formation processes and their reliable microscopic evidence in an artifact can help to define ceramic production phases, including the circumstances for paste preparation, firing, and abandonment or disuse stages. At the same time, this microscopic evidence reflects the preferential selection of certain types of materials. Overall, the use of these resources is part of an ecological footprint related to questions of sustainability in Maya civilization.

The results of a hierarchical morphogenetic, physicochemical, and mineralogical study of the Ryshkovo full-profile texture-differentiated paleosol of the Mikulino Interglacial from the section at Aleksandrov quarry in Kursk oblast are discussed. The correlation analysis of the stratigraphy of this section with global geological records made it possible to determine the position of the Ryshkovo paleosol in the chronostratigraphic system of the Late Pleistocene and to attribute it to stage MIS 5e; the duration of pedogenesis for this paleosol was no more than 12–15 ka. The results of the study indicate that the Ryshkovo paleosol is close in its properties to the Holocene soddy-podzolic soils of the East European Plain. No direct evidences in favor of the former interpretation of this paleosol as a lessivated soil genetically close to Luvisols of nemoral broadleaved forest of Central Europe have been found. The difference between the paleosol of the Mikulino Interglacial and the modern soddy-podzolic soils is mainly related to the distribution of clay coatings. In the upper part of the illuvial horizon of Mikulino paleosol, clay coatings are few in number, and typical tongues of podzolized (albic) material are absent in the profile. At the same time, silty coatings (skeletans) are abundant even in the lower part of the illuvial horizon. In general, the Mikulino paleosol is characterized by a smaller diversity of clay pedofeatures. These differences might be related to less contrasting fluctuations of the environmental conditions in the second half of the Mikulino Interglacial, to the periodical renewal of the eluvial part of Mikulino paleosol by erosional and accumulative processes, and to the absence of anthropogenic impacts on the soil during the Mikulino Interglacial. The burying of the Ryshkovo paleosol took place due to the intense development of erosional processes induced by the contrasting climatic events at the end of the interglacial period accompanied by catastrophic forest fires and sharp cooling of the climate upon the transition to the Valdai glaciation.

Soils and sediments composing Tell Kortik Tepe (Epipaleolithic, Turkey) and Tell Yunatsite (Chalcolithic (Eneolithic), Bulgaria) have been studied with the aim to gain a better insight into their microfabrics, determine the composition of anthropogenic artifacts, and, on this basis, to analyze similarities and distinctions between these objects and the modern soils of urban areas. The methods of micromorphology, scanning electron microscopy with an energy dispersive X-ray microanalyzer, X-ray fluorometry, and other techniques to determine the chemical and physical properties of the soils and sediments have been applied. Two paleosols have been identified in Tell Yunatsite with a total thickness of 9 m: the paleosol buried under the tell and the paleosol in its middle part. Sediments of Tell Kortik Tepe have a total thickness of up to 5 m; their accumulation began at the end of Pleistocene over the surface of buried paleosol. The cultural layer of the tells consists of construction debris mainly represented by a mixture of clay and sand and of domestic wastes with the high content of phosphorus. The major source of phosphorus is calcium phosphate (apatite) of bone tissues. The abundance of various anthropogenic materials in the sediments is clearly seen in thin sections. Even in the paleosols developed within the cultural layer (the mid-profile paleosol in Tell Yunatsite), the amount of microinclusions of bone fragments, charcoal, and burnt clay (ceramics) is very high. Micromorphological data indicate that up to 50% of the layered material filling an Epipaleolithic construction in Tell Kortik Tepe consists of the anthropogenic inclusions: bone fragments, charcoal, etc. The features of pedogenic transformation are present in the sediments. Such sediments can be classified as synlithogenic soils similar to the modern Urbic Technosols. It is shown that the formation of paleosols and sediments of Tell Kortik Tepe took place under extreme environmental conditions—arid climate of the latest Pleistocene climate cooling phase (the Younger Dryas, Tell Kortik Tepe)—and intensive anthropogenic loads (tells Kortik Tepe and Yunatsite).