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Soil erosion and the loss of soil organic carbon (SOC) pools are considered serious environmental problems in undulating landscapes on loess covers, accompanied in some areas, such as south Poland, by the physical degradation of chernozemic soils. The aim of the present study was to identify the scale and reasons for spatial variation of the SOC pools in the intensely cultivated Luvic Phaeozems in one of the unique patches of chernozemic soils in Poland. This study, carried out in a soil catena located in the undulating Carpathian Foreland in south-east Poland, has demonstrated that the SOC pools can greatly differ on a very small scale, even in relatively less differentiated landscapes and in soils classified into the same group. The scale and reasons for the differentiation of the SOC pools depend on the method (depth) of calculation. The spatial differences were smaller and were mainly related to the SOC concentrations and the bulk density of the topsoil horizons, when calculated for depths of 0–30 cm and 0–50 cm. On the other hand, the SOC pools calculated for the 0–100 cm soil layer differed most significantly between the profiles in the catena, representing a continuous growing trend from the uppermost towards the lowermost part of the catena, and were clearly related to the total thickness of the humus horizon(s). The latter findings confirm that sheet erosion has a major impact on the spatial variation of SOC pools in an agricultural landscape. However, soil morphology and the distribution of SOC across the soil profiles suggest additional influences from historical pedogenesis and modern farming technology. The presence of black, thick and humus-rich chernic horizons in all soils across the catena indicates that modern farming must not degrade the soils, but, on the contrary, it can help in the restoration of even neo-formation of chernozemic soils (Phaeozems), if oriented towards the conservation of humus content, soil structure, and biological activity. [ABSTRACT FROM AUTHOR]

We have studied geochemical features of organo-accumulative soils (Eutric Regosols (Loamic, Ochric)), Cambic Someric Phaeozems (Loamic)) widely spread in the soil cover of subtaiga and subtaiga-forest-steppe light coniferous forests and forming the lower boundary of the forest zone in the mountains of Northern Mongolia. Data on the microelement composition of soil-forming rocks are given; the paragenetic association of trace elements in them is composed of Pb, Cu, Zn, Co, V, Cr, Ni, Mn, Mo, Ba, Sr, Zr, and B. The residual and redeposited weathering crusts of igneous rocks are enriched with Zn, Cr, Mo, and B as compared to the mean content of these elements in the lithosphere, but they contain less Pb, Co, Mn, Ba, Sr, and Zr. The residual and re-deposited weathering crusts of calcareous rocks are enriched in Pb, Cu, Zn, V, Cr, Sr, and B, and are impoverished in Co, Ni, Mn, Mo, Ba, and Zr. The morphological, physicochemical and chemical properties of soils, as well as the content and radial distribution of trace elements in soils are discussed. The data obtained testify to the accumulation of most trace elements in the surface organic and humus-accumulative soil horizons. This is associated with the heterogeneity of soil-forming rocks and with the effect of soil processes, which cause the accumulative redistribution of elements and their deposition at organic-sorption and carbonate geochemical barriers. It is shown that the studied soils differ not only in the absolute contents of trace elements, participating in the biological cycle, but also in the intensity of their involvement in biogenic migration. [ABSTRACT FROM AUTHOR]

The results of studies of mountain-meadow soils of the Crimean Mountain plateaus (yailas) within the range of heights from 580 to 1,493 m a.s.l. are presented. The aim of the research is a comparative analysis of the full-profile soils of the mountain meadows distributed on the western and eastern parts of the Main Ridge of the Crimean Mountains and their correspondence to similar soils of nearby mountain ranges. According to the results obtained, the soils of the western yailas are classified as Phaeozems and Umbrisols, while the eastern ones are mostly classified as Chernic Phaeozems. Chernic Phaeozems differ from Phaeozems and Umbrisols by higher values of the humification rate and the optical density of humic acids. In the humus horizons of Phaeozems and Umbrisols, the average values of the of humification rate varied from 21 to 31 percent, and Chernic Phaeozems from 27 to 34 percent. The optical density varied from 12.7 to 18.7 in Phaeozems and Umbrisols, and from 22.2 to 24.2 in Chernic Phaeozems. The climatic feature of the western yailas is the predominance of winter precipitation, or their relatively uniform distribution between warm and cold seasons, while at the eastern yailas the precipitation of the warm season prevails which may be responsible for the revealed differences in soil properties.

This research presents the characteristics and inferred evolution of post-bog soils developed in the Last Glacial Maximum area of northwestern Poland near the southern Baltic coast. The study involved a total of five sites near existing lakes in NW Poland. In total, 21 soil pits were described and sampled and 17 piezometers were installed. In soil samples chemical and physical properties were determined. During the hydrological year the water level was checked and chemical properties of water were determined, the floristic composition at each location was also carried out. Mineralisation of post-bog soils initiated by dehydration leads to the decomposition of organic surface layers and an increase in CaCO3 content as well as mineral non-lime components at the expense of organic matter. A sequence of five soil types occurs in this landscape: Sapric Histosols (Limnic), Drainic Histosols (Calcaric, Limnic), Histic Gleysols (Murshic), Umbric Gleysols (Hyperhumic), Gleyic Phaeozems (Hyperhumic) that represent individual stages of soil genesis. Differences between the chemical properties of soils are apparent between organic vs organic-mineral and mineral layers. Man-induced drainage of post-bog soils changes their physical parameters. Bulk density increase and water retention decrease. The fluctuation of groundwater determines the moisture content of post-bog soils and affects the species composition of vegetation. Chemistry of groundwater is shaped mainly by the construction of catchment and the nature of its use, however, it is modified as a result of the inflow of macronutrients released during organic matter mineralisation processes and leaching of exchangeable forms from the sorption complex.

The soil fertility is induced and sustained by the soil constituents. In this respect, the clay is one of the main nutrient bearing. The presence of the clay pedofeatures (coatings and pore infillings) generally shows an intense leaching process of the constituents from the rooting zone. The leaching process also includes the nutrients depletion, and consequently a pH decreased. The results of the micromorphological investigation of the Phaeozems shows the presence of many impure clay coatings (consisting of clay and a large amount of colloidal humified organic matter), in all the pedogenetic horizons. The richness of the humic substances created a favourable environment for the microbiota. As a result, many microorganisms developed on the impure clay coatings, the evidence being the presence of many fungi spores, as well as the black mycelium of the mycorrhizal fungi on these coatings. The micromorphological investigation pointed out another facet of the intimate mechanisms of the Phaeozems related to fertility (as one of the most important ecosystem services). [ABSTRACT FROM AUTHOR]

Soil texture is a key physical property that affects the soil's ability to retain moisture and nutrients. As a result, it is of extreme importance to conduct remote sensing monitoring of soil texture. Songnen Plain is located in the black soil belt of Northeast China. The development of satellite imagery in remote sensing technology enables the rapid monitoring of large areas. This study aimed to map the surface soil texture of cultivated land in Songnen Plain using Sentinel-2 images and Random Forest (RF) algorithm. We conducted this study by collecting 354 topsoil (0–20 cm) samples in Songnen Plain and evaluating the effectiveness of the bands and spectral indices of Sentinel-2 images and RF algorithm in predicting soil texture (sand, silt, and clay fractions). The results demonstrated that the 16 covariates were moderately and highly correlated with soil texture. And, Band11 of Sentinel-2 images could be used as the corresponding band of soil texture. For sand fraction, the Sentinel-2 images and RF algorithm's Coefficient of Determination (R2) and Root Mean Square Error (RMSE) were 0.77 and 10.48%, respectively, and for silt fraction, they were 0.75 and 9.38%. Sand fraction decreased from southwest to northeast in Songnen Plain, while silt and clay fractions increased. We found that the Songnen Plain was affected by water erosion and wind erosion, in the northeast and southwest, respectively, providing reference for the implementation of Conservation Tillage policies. The outcome of the study can provide reference for future soil texture mapping with a high resolution. [ABSTRACT FROM AUTHOR]

An important part of soil science research is the classification of soils. Numerous soil scientists have paid special attention to various dependencies related to the content and distribution of iron forms in the soil profile. This allows the taxonomic unit to be determined according to soil classifications. The research objective was to evaluate the distribution of iron forms as an indicator of soil-forming processes in four profi les of arable black earths. The research subject was soils formed from glacial sediments in the Chełmno Lake District (northern Poland). They were determined by morphological description to be Phaeozems representing four subtypes: Haplic Phaeozem, Luvic Gleyic Phaeozem, Gleyic Phaeozem and Gleyic (Cambic) Phaeozem. Soil horizons were described according to FAO guidelines. The soil samples were analysed for the content of free iron oxides (Fed) according to Mehra and Jackson's method, as well as the content of amorphous iron oxides, (Feo) according to Schwertmann's method. Based on the content of Fed and Feo, the content of crystalline iron oxides (Fec) was calculated using the formula: Fec = Fed-Feo and the iron oxides activity index was calculated from the Feo/Fed ratio. The content of Fet was highest in the Bt horizon of profile II. In individual profi les, Fed content was highest in the Bt horizon of gleyic Phaeozem and the AB horizon of gleyic (cambic) Phaeozem. In Luvic Gleyic Phaeozem and Gleyic (Cambic) Phaeozem iron was removed from the surface horizon to be accumulated in the illuvial horizon. The uniformity of content of total iron and its free iron oxides in the parent material of the analysed soils indicates its genetic homogeneity. The release of iron in the Ap horizon is characteristic of chemical weathering. The relationship between the content of Feo and Fed determines the degree of crystallization of free iron oxides. Based on the statistical analysis, a significantly positive correlation between the content of clay fraction and all the iron forms determined was found. All the profi les were characterized by similar degrees of weathering of the soil material, which was determined on the basis of the Fed/Fet ratio. The soils also demonstrate a low value of iron mobilization, as confirmed by the values of the Fed/Fet ratio. Determining iron forms and interpreting analysis results help in the correct classification of soils, because the distribution of iron forms in soil profiles depends mainly on pedogenesis. [ABSTRACT FROM AUTHOR]

The results of studies of mountain-meadow soils of the Crimean Mountain plateaus (yailas) within the range of heights from 580 to 1,493 m a.s.l. are presented. The aim of the research is a comparative analysis of the full-profile soils of the mountain meadows distributed on the western and eastern parts of the Main Ridge of the Crimean Mountains and their correspondence to similar soils of nearby mountain ranges. According to the results obtained, the soils of the western yailas are classified as Phaeozems and Umbrisols, while the eastern ones are mostly classified as Chernic Phaeozems. Chernic Phaeozems differ from Phaeozems and Umbrisols by higher values of the humification rate and the optical density of humic acids. In the humus horizons of Phaeozems and Umbrisols, the average values of the of humification rate varied from 21 to 31 percent, and Chernic Phaeozems from 27 to 34 percent. The optical density varied from 12.7 to 18.7 in Phaeozems and Umbrisols, and from 22.2 to 24.2 in Chernic Phaeozems. The climatic feature of the western yailas is the predominance of winter precipitation, or their relatively uniform distribution between warm and cold seasons, while at the eastern yailas the precipitation of the warm season prevails which may be responsible for the revealed differences in soil properties. [ABSTRACT FROM AUTHOR]

This research presents the characteristics and inferred evolution of post-bog soils developed in the Last Glacial Maximum area of northwestern Poland near the southern Baltic coast. The study involved a total of five sites near existing lakes in NW Poland. In total, 21 soil pits were described and sampled and 17 piezometers were installed. In soil samples chemical and physical properties were determined. During the hydrological year the water level was checked and chemical properties of water were determined, the floristic composition at each location was also carried out. Mineralisation of post-bog soils initiated by dehydration leads to the decomposition of organic surface layers and an increase in CaCO3 content as well as mineral non-lime components at the expense of organic matter. A sequence of five soil types occurs in this landscape: Sapric Histosols (Limnic), Drainic Histosols (Calcaric, Limnic), Histic Gleysols (Murshic), Umbric Gleysols (Hyperhumic), Gleyic Phaeozems (Hyperhumic) that represent individual stages of soil genesis. Differences between the chemical properties of soils are apparent between organic vs organic-mineral and mineral layers. Man-induced drainage of post-bog soils changes their physical parameters. Bulk density increase and water retention decrease. The fluctuation of groundwater determines the moisture content of post-bog soils and affects the species composition of vegetation. Chemistry of groundwater is shaped mainly by the construction of catchment and the nature of its use, however, it is modified as a result of the inflow of macronutrients released during organic matter mineralisation processes and leaching of exchangeable forms from the sorption complex. [ABSTRACT FROM AUTHOR]

This study is focused on an evaluation of some important soil properties as a result of the genesis of mollic soils which are located outside of the main Chernozem regions in Slovakia. Several soil profiles selected from the Soil Monitoring Network in Slovakia were evaluated and interpreted. Unified analytical procedures used in soil monitoring system have been applied. Following soil indicators: pH, humus content, and qualitative components as humic acids (HA) and fulvic acids (FA) as well as the fractional composition of HA, the content of labile carbon (CL), potentially mineralisable nitrogen (Npot) have been analysed. Based on obtained results in more details, it may be said that the dark-coloured soils in non-Chernozem regions opposite dark-coloured soils in Chernozem regions have a higher content of labile carbon and higher index of lability as well as higher CL: Npot ratio. This indicator seems to be more significant than the often used C/N ratio. In addition, the darkcoloured soils in non-Chernozem regions are characteristic with higher content of aliphatic carbon as well as lower content of carboxylic groups (-COOH) and lower value of the optical parameter (E1% 6). These indicators in more detail are of higher interpretation value for a better evaluation of dark-coloured soils in non-Chernozem regions compared with similar soils in Chernozem regions.

The paper deals with calcareous soils in Golo Bardo Mountain in western Bulgaria. Until now no significant studies have been made for the soils of Golo Bardo Mountain. Our goal was to give assess data for their soil features, characteristics, main diagnostic indicators and properties in order to define the soil formation processes, as well as their complete morphological description. Eight soil profiles were studied in different parts of the mountain. Due to the carbonate soil-forming rocks, the leaching processes in these soils are extremely weak and it is usually difficult to distinguish the individual genetic horizons. In relation to the soil-forming carbonate rocks in the area, we distinguish two main soil units. The studied soils are Leptosols or Phaeozems with good fine-granular structure, dark humus horizon (mollic) and shallow soil profile Ak-ACk-CRk, lying on hard or weathered carbonate rock. In the studied mountain area with different elevation, the surface mollic horizon is usually shallower and very often eroded with fragments from calcareous rock. The soils are well stocked with organic matter. The amount of organic carbon in the surface A horizon varied from 7.4 % to 2.8%. The calcium dominates in exchange capacity of the soil over all other cations. There is no exchange acidity in these soils, except small amounts in the soil surface and in litter. The content of carbonates is an important soil-forming feature of these soils.

The dark-humus soil type was included in the updated legend of the Soil Map of the Russian Federation at scale 1 : 2.5 M, converted to the system of Soil Classification of Russia. The soil profile starts with the dark-humus horizon gradually merging to the parent rock; any mid-profile diagnostic horizons are absent. Large areas of dark-humus soils are found in the forest-steppe, steppe and taiga zones of the European Russia, Western and Central Siberia, in the Trans-Baikal region, the Altai-Sayany Mountains, and the Caucasus. The type of dark-humus soils comprises both mesomorphic soils (of normal moisture conditions) and soils with additional surface or ground-water moisture. The main prerequisites for the formation of dark-humus soils are, on the one hand, the climatic conditions favorable for the dark-humus horizon formation, and, on the other hand, parent material - mostly derivates of hard rocks, restricting the development of mid-profile diagnostic horizons. In the updated map, the following initial legend units are partially or completely converted to dark-humus soils: several units of chernozems, dark-gray forest and gray forest non-podzolized soils, soddy-taiga base-saturated and slightly unsaturated soils, several mountain soils, a significant part of soddy-calcareous soils, as well as some mountainous forest-meadow soils. The diversity of dark-humus soils subtypes is determined by secondary carbonate features, weak signs of clay accumulation and podzolization, alteration of the mineral mass, gley and cryogenic phenomena.

[Display omitted] • The total soil organic C stored in Brazil's black soils is about 0.35 Gt. • Changes on C stock are not explained by climate and land use in national-scale. • Low C/N ratio values indicate the dominance of microbial-derived compounds. • Organo-mineral interactions were the main mechanism of SOC stabilization. • The potential of C stock stabilization of Brazil's black soils is about 0.25 Gt. Climate and land use are recognized as two of the main drivers of changes in soil organic carbon (SOC) on a global scale. Both factors play an important role in understanding SOC sequestration and mitigation of climate change. Particularly important, black soils are mineral soils with high SOC contents and high natural fertility and play an important role in national and global food and climate security. Here, we used a database of 90 black soils in Brazil − under different climate and land use conditions across the country − to test the hypothesis that C stock is richer in wetter climate conditions and that agricultural land use reduces C stock and the percentage of carbon saturation (PCS%). Climate data were obtained from the National Oceanic Atmospheric Administration (NOAA) and used to classify Thornthwaite's climate. The land use information was obtained in the MapBiomas platform and was grouped into three major types: cropland, pasture, and native vegetation. The nonparametric Kruskal-Wallis test showed no differences for C stock, C/N ratio, and PCS% for both land use and climate. The low C/N ratio and the strong correlation between Ca2+, CEC, clay, and SOC suggest that organo-mineral interactions − which are stronger in soils with high-activity clays (e.g., Chernozems, Kastanozems, and Phaeozems) − promotes greater stabilization of the SOC and its long-term persistence and, thus being less sensitive to variations in climate and land use. Considering the total area of approximately 3.7 × 106 ha and the average value of C stock of 93.2 Mg/ha, the total SOC stored in Brazil's black soils is in the order of 0.35 Gt, and the carbon stock stabilization potential is 0.25 Gt. Our results highlight the potential of Brazil's black soils to promote carbon sequestration and climate change mitigation. [ABSTRACT FROM AUTHOR]

Summary: A number of studies across sub-Saharan Africa have recently reported poor crop responses and low agronomic use efficiencies of applied nitrogen (AEN), phosphorus (AEP) and potassium (AEK). However, the conditions under which non-responsiveness occurs, its underlying causes and its probability of occurrence on different soil types are not well understood. Using data from 542 sites and 14 soil types in 23 African countries, we provide novel insights into the linkage between lack of response to applied N, P and K, the mineralogy of soils and their resilience to erosion. We estimated mean responses as well as the probabilities (ϕ) of no response in terms of response ratio (RR), yield gain (YG) and agronomic efficiency. Here we defined 'no response' as zero agronomic response to fertilizer inputs in a given site and year indexed by either RR ≤ 1, AEN ≤ 0, AEP ≤ 0 or AEK ≤ 0. The highest risks of no response were recorded on the iron-rich Plinthosols (ϕ = 0.26) followed by the aluminium-rich Alisols (ϕ = 0.16) and the erosion-prone Lixisols (ϕ = 0.16) and Leptosols (ϕ = 0.13). In terms of yield gains, the highest risk of low response (i.e., YG ≤ 0.5) was recorded on Alisols (ϕ = 0.47) and the lowest on Fluvisols (ϕ = 0.05). Cambisols, Fluvisols, Luvisols and Nitisols were deemed highly responsive to NPK fertilizer. The risks of no response were significantly higher on soils derived from siliceous than mafic parent materials, soil types with low resilience to erosion, soils with low-activity clays and high P fixation capacity. It is concluded that maize grain yields can exceed 3 t ha-1 with high probability (ϕ > 0.80) on Andosols, Nitisols and Vertisols, but with very low probability (ϕ < 0.30) on Alisols and Arenosols. It is also concluded that across soil types and agroecological zones, the risk of no response is up to two times more on farmers' fields than on research stations. Here, we discuss the implications of these finding for the design and location of future agronomic trials. We also provide insights to guide the targeting of fertilizer subsidies where nutrients can be more efficiently used. [ABSTRACT FROM AUTHOR]

The Soil Science Society of Poland has elected chernozem to be the Soil of the Year 2019. Although chernozems cover less than 2% of Poland, they have high importance for agriculture due to their productivity and play a specific scientific role for understanding of soil development and functioning in an environment. Chernozems are also crucial for the reconstruction of Neolithic agriculture development and human impacts on soil and landscape. This introductory paper presents (a) a specific definition of chernozem in Poland, connected with a separate distinction of black earths and colluvial chernozemic soils; (b) a review of the present and former classification schemes for chernozems in Poland and their correlation with international soil classification systems (WRB and Soil Taxonomy); (c) the spatial distribution of chernozems in Poland, their agricultural evaluation and threats for chernozems’ quality and future existence related to intense land use.

The purpose of the work was to characterize the variously used humus in the south-eastern part of the Lublin region. The basic research material were data taken from the literature on the subject. Standard soil science methods were used in the study. The humus level of humus varieties ranged from 30 to 80 cm. The researched molds were formed from loess deposits, which most often showed graining of clay dust. Organic carbon content in humus levels did not exceed 2.9%. The surface levels of the analyzed molds showed clear decalcification. The CaCO3 content in the loess mother rock was a maximum of 15.5%. These are soils with high saturation of the sorption complex with basic cations. The content of available phosphorus and potassium in humus levels was low and medium. According to Systematics of Poland’s soils (2019), the analyzed molds mainly represented leached molds and typical molds, while according to the international soil classification WRB (IUSS Working Group WRB 2015) they are primarily Phaeozems. All the analyzed humus plants belong to soils with the highest utility value. Phenomena lowering the quality of molds in the Lublin region related to human activity are the use of improper agrotechnics, and above all water surface erosion. The unfavorable processes are favored by the undulating terrain and the grain size of the soils studied, characteristic for this area.

Chernozemic soils are distinguished based on the presence of thick, black or very dark, rich in humus, well-structural and base-saturated topsoil horizon, and the accumulation of secondary carbonates within soil profile. In Central Europe these soils occur in variable forms, respectively to climate gradients, position in the landscape, moisture regime, land use, and erosion/accumulation intensity. “Typical” chernozems, correlated with Calcic or Haplic Chernozems, are similarly positioned at basic classification level in the national soil classifications in Poland, Slovakia and Hungary, and in WRB. Chernozemic soils at various stages of their transformation are placed in Chernozems, Phaeozems or Kastanozems, supplied with respective qualifiers, e.g. Cambic, Luvic, Salic/Protosalic, Sodic/Protosodic etc. Some primeval Chernozems thinned by erosion may still fulfil criteria of Chernozems, but commonly are shifted to Calcisols. Soils upbuilt (aggraded) with colluvial additions may also retain their original placement in Chernozems, getting supplementary qualifier Colluvic. “Hydromorphic” chernozemic soils, in many CE systems are placed as separate soil type (“czarne ziemie” or “čiernice”) at the same level with “typical” chernozems. Classification of these soils in WRB depends on the presence of chernic horizon, depth of secondary carbonate accumulation and depth of gleyic/stagnic properties, and may vary from Gleyic/Stagnic Chernozems/Phaeozems to Mollic Gleysols/Stagnosols. Although WRB classification differs from national classifications in the concepts and priorities of classification, it provides large opportunity to reflect the spatial variability and various stages of transformation/degradation of chernozemic soils in Central Europe.

The soil cover of the forest-steppe and steppe zones of the East European Plain is characterized by diverse soil combinations revealed during large-scale and detailed soil mapping against the background of a traditional zonal sequence of dominant automorphic soils alternating from the north to the south and clearly displayed on small-scale soil maps. The composition, configuration and functioning of particular soil cover patterns are determined by the soil forming factors acting within a given area. The elementary soil areas (detailed scale) and elementary soil cover patterns maps (large scale) of the Central Russian, Kalach, and Volga Uplands are created by both traditional and digital soil mapping methods. Low-contrasting soil combinations with the background Haplic Chernozems (Loamic or Clayic, Pachic) alternating with zooturbated Haplic Chernozems (Loamic or Clayic, Pachic) on convex elements of the microtopography and Luvic Chernozems (Loamic or Clayic, Pachic) on concave elements of the microtopography prevails under conditions of thick clay loamy parent materials and free drainage. Under conditions of shallow embedding by low-permeable clayey sediments, the soil cover includes Chernozems or Chernic Phaeozems with stagnic features in some part of the soil profile or even Mollic Stagnosols. The presence of shrink-swell clays of different ages leads to the formation of Bathyvertic Chernozems, Vertic Chernozems, Vertic Chernic Phaeozems and/or Pellic Vertisols. The presence of soluble salts in the parent material leads to the development of solonetzic soil complexes consisting of Protosodic or Sodic Chernozems and different types of Solonetzes.

Vertisols are characterized by high content of clay fraction that affects their specific morphological and physical features. The shrink-swell phenomena of clayey materials under specific moisture regime cause formation of cracks, wedge-shaped structural aggregates and slickensides on aggregate surfaces. It was formerly believed that these soils can be found only in tropical/subtropical zones, thus Vertisols have not been expected to form under temperate climate of Central Europe. As a result, Vertisols are insufficiently recognized and documented on soil maps in Poland, including the Lower Silesia region. The aim of this study was to examine soils developed on clayey parent materials near Strzelin, focusing on their morphology, properties and classification issues. There was confirmed that soils developed from Neogene clays have vertic and mollic horizon, accompanied by stagnic or gleyic properties. However, not all soils fulfil the criteria for Vertisols due to the presence of surface or subsurface coarser-textured (sandyor silty-textured) layers. Native differentiation of parent material and geomorphological processes were found the main factors, which control the spatial mosaic of Vertisols and black earths (Chernozems or Phaeozems).

Numerous experiments with nanoparticles have recently led to a better understanding of the migration of colloids and larger particles in soils. However, it remains unclear how colloidal particles migrate in soil horizons without macropores, and whether they can move with the flow of capillary water. In this article, we tested the hypothesis that colloidal particles can be transported by water flow in capillary-sized soil pores. To test our hypothesis, column experiments with platinum nanoparticles were carried out. The columns contained undisturbed monoliths from the Luvisols and Phaeozems soil horizons in the southeast of Western Siberia. The lower part of the soil columns was immersed in a colloidal solution with platinum nanoparticles. Thus, we checked whether the nanoparticles would rise to the top of the columns. Platinum nanoparticles are a usable tracer of colloidal particle migration pathways. Due to the minimal background concentrations, platinum can be detected by inductively coupled plasma mass spectrometry (ICP-MS) in experimental samples. Due to their low zeta potential, nanoparticles are well transported over long distances through the pores. Our experiments made it possible to establish that the process of the transfer of nanoparticles with a flow of capillary water is possible in almost all the studied horizons. However, the transfer distances are limited to the first tens of centimeters. The number of migrating nanoparticles and the distance of their transfer increase with an increase in the minimum moisture-holding capacity and decrease with an increase in the bulk density of soil horizons and an increase in the number of direct macropores. The migration of nanoparticles in capillary pores is limited in carbonate soil horizons. The transfer of colloidal particles through soil capillaries can occur in all directions, relative to the gravity gradient. Capillary transport plays an important role in the formation of the ice composition of permafrost soils, as well as in plant nutrition. [ABSTRACT FROM AUTHOR]

The soils of archaeological sites on river floodplains with contrasting history of the Holocene soil evolution in the south and north of the forest-steppe zone on the Central Russian Upland have been studied. The conditions for the meadow-chernozemic soil development on the high floodplain in the lower course of the Savala River (Voronezh oblast) were most favorable in the Early Holocene (10.3–9 ka BP); 9 ka BP, the soil humus profile was two times deeper than it is today. The most intensive alluvial sedimentation (0.5 mm/yr) was typical of the Late Pleistocene and Early Holocene (11–8.3 ka BP), while in the Middle and Late Holocene, the rate of the upward growth of soils decreased to 0.05 mm/yr. The underdevelopment of modern chernozemic-meadow soil profiles suggests an alternation of accumulation and denudation (including deflation) of fine-earth particles on the soil surface in the Late Holocene. On the floodplain in the upper course of the Oka River (Orel oblast), the development of a monogenetic profile of medium-deep leached chernozems with the humus content of more than 7% and humus stocks in the upper meter of at least 450 t/ha took place in the Holocene. Before the beginning of the second millennium AD, the alluvium sedimentation rate was no more than 0.02 mm/yr; in the recent millennium, it has increased up to 1 mm/yr. The specificity of changes in the bioclimatic conditions and spatiotemporal specificity of anthropogenic disturbances of the natural environment caused the metachronous Holocene evolution of floodplain soils in the studied regions. The importance of radiocarbon dating of organic matter of uneven-aged soils for paleopedological and paleogeographic reconstructions is shown. [ABSTRACT FROM AUTHOR]

Studies on organic matter have always been an important part of soil environment characterization. However, an extraction of humic substances from the organo-mineral complexes is difficult and requires special procedures. Sodium hydroxide, sodium pyrophosphate and sulfuric acids are among the basic extractants. However, its application in various order, combinations and concentrations arises question on the comparability of the results obtained from various methods. The aim of the review was to compare the major fractionation procedures according to Tiurin, Kononowa/Belczikowa, Boratyński/Wilk, and Duchaufour/Jacquin, and the composition of soil humus as investigated by these methods, using the published data for chernozemic soils from various regions of Poland. The comparison confirmed, that these major fractionation procedures are hardly comparable in chemical terms due to differences in extraction environment. However, taking into account the declared binding strength of extracted humus fractions to the mineral soil compounds, the methods of Tiurin and Boratyński/Wilk gave the most compatible results. In general, all applied methods indicated a predominance of the humus fractions weakly and more strongly bound to non-silicate soil compounds (apart from the high contribution of humins/non-extractable residuum). Considering all multistage and long lasting procedures applying different reagents in various concentration, the best results can be achieved with method of Tiurin. At the same time authors suggest that more advanced studies concerning composition, structure or other properties of extracted humic substances using the non-invasive procedures need to be carried out. [ABSTRACT FROM AUTHOR]

The loess in the Danubian plain is rich of nutrients and there is situated the south border of so called ―corn belt of Europe‖, where are the most fertile soils of Balkan Peninsula. There are five main typical soil types spread over loess - Chernozems, Phaeozems, Kastanozems, Regosols and Calcisols. There is also a big diversity in the content of basic nutrient elements – it varies between low and high content of organic carbon and mobile forms of nitrogen, phosphorous and potassium. As a whole there is shortage of phosphorus in all soil types. Soils over loess are characterized by a surface layer that is rich in organic matter, minerals and nutrients with abundant natural grass vegetation and high fertility soil types such as Chernozems, Phaeozems and Kastanozems. Eroded and shallow soils such as Regosols and Calcisols have low quantities of major nutrient elements as mobile nitrogen, phosphorus, and total organic matter, consequently their fertility is low.

Carbonate-rich soils are characterized by great diversity in content of carbonate and non-carbonate mineral substances in soil substrate which largely influences soil properties. The study presents the analysis results of four soil profiles located at the area of Pieniny National Park. The aim of this study was to characterize and classify the soils developed from the mixture of carbonate and carbonate-rich rock material, formerly classified as pararendzinas. It was achieved by determination of morphological, physical, and chemical properties, as well as mineralogical composition of selected carbonate-rich soils occurring in the Polish part of the Pieniny Mts. Soils were classified as typical chernozemic rendzina (P1), typical eutrophic brown soils (P2, P4), as well as typical pararendzina (P3) according to Polish Soil Classification (2011).

Maximum permissible concentrations for chemical elements in soils (MPCs) of Russia, Germany, Canada, the Netherlands and the USA are compared. In Russia, general sanitary, water-transferred and translocation MPCs are created; in Germany, general sanitary and translocation, and in the Netherlands, the USA and Canada, general sanitary. It is found that the Russian MPCs for total contents of chemical elements are adequate for Mn and V, American, for Co, Cu, and Pb; Dutch, for Pb and Zn; Canadian, for Ba, Co, Ni, Pb, V, and Zn, and German, for Cr, Ni, and Pb by taking into account the typical levels of elements in the background soils across the world. The methodologically closest Russian and Dutch standard rates of total contents of chemical elements are compared in this paper with the typical levels for background Retisols gleic, Phaeozems, and Chernozems in the center of Western Siberia. It is established that use of the Dutch MPCs for the soils under study gives fewer cases of false Pb pollution, but in all the soils under consideration the Dutch MPCs for Ba is exceeded. False pollution by total Zn is observed in the top-soil; by Cr, Cu and V, in subsoil horizons of Retisols gleic as well as by Cr, Ni and V, in most samples of Phaeozems and Chernozems. It is concluded that for the soils under consideration the utilization of Russian MPCs gives fewer cases of false pollution by V. But in the background Retisols gleic, Russian MPCs for Mn and Pb accumulated in the biogeochemical barrier in the top-soil horizons are exceeded. Russian MPCs for metal mobile fraction are the most correct for Co, Cr, Cu, Ni and Pb. The MPCs for mobile fraction of biogenic Mn and Zn are underestimated. Background levels (mg/kg in subindex) of total concentration (mobile fraction extracted by acetate-ammonium buffer) are proposed for Ba404–515, Co12–19(0.001–0.23), Cr143–188(0.001–0.72), Cu32–41(0.01–0.72), Mn423–874(0.09–64), Ni30–62(0.003–1.3), Pb18–27(0.003–0.87), V112–170 иZn55–104(0.004–0.42) in Retisols gleic on Tobol Upland, Phaeozems on Ishym Upland, and Chernozems in the Trans-Ural region. [ABSTRACT FROM AUTHOR]

A method for the digital mapping of phosphorus (total, organic, and labile) content in soils has been developed using spatially distributed NDVI values calculated from Landsat 8 image (30-m resolution). A comparative analysis of the phosphorus content has been performed in high- and medium-humous soils. Medium-humous soil (agrochernozems, agro–dark gray) has been found to have lower contents of the total (by a factor of 1.1) and organic (by a factor of 1.5–1.7) phosphorus compared with high-humous agrochernozems. The reverse trend has been identified for the labile phosphorus; that is, medium-humous soils twice exceeded the high-humous agrochernozems in its content. The plants have been proven to have a sufficient supply of phosphorus, since the element content in the aboveground phytomass of the oat-pea mixture was in the optimal range of 0.23–0.5% on a dry weight basis. No phosphorus deficiency symptoms have been detected in the plants by visual diagnostics. No correlation has been found between the phosphorus content in plants, aboveground phytomass stock of the oat-pea mixture and NDVI. [ABSTRACT FROM AUTHOR]

Soils of the Pavlovsk Park–the largest landscape park in Europe—have been studied, and large-scale mapping of the soil cover of the main areas of the park has been performed. Limnoglacial and alluvial deposits are the predominant soil forming materials in the park. Iron-illuvial soddy podzols (Umbric Podzols) predominate among the natural soils of the park, and gray-humus stratozems (Hortic Anthrosols) underlain by the limnoglacial deposits and/or by the buried soils are the main human-transformed soils of the park. The areas of urbostratozems are mainly confined to the Slavyanka River valley. The thickness of human-created stratified layer of stratozems and urbostratozems varied from 40 to 120 cm. Soils with an acid reaction predominate in the park, except for the Slavyanka River valley, where most of the soils have a neutral or an alkaline reaction. The organic carbon content in topsoils ranges from 0.9 to 4.4%. The majority of the park soils are characterized by the low content of available potassium and by the considerable variability in the content of available phosphorus. The results of the soil survey may serve as the basis for further monitoring studies and be helpful in the development of measures for the conservation and restoration of the tree stands in the park. [ABSTRACT FROM AUTHOR]

Among residents of the Bryansk and Gomel regions of Russia and Belarus, who were exposed to the so-called "iodine attack" as a result of the 1986 Chernobyl Nuclear Power Plant accident, there was a sharp increase in thyroid disease. Therefore, the natural iodine deficiency in soils was an important additional risk factor that could cause adverse reactions primarily among children, for whom the incidence of thyroid cancer in Belarus increased by 76 times. Potatoes belong to one of the main ration-forming foods for local population. In this regard, in 2007–2017, 97 settlements were surveyed in the affected areas, in which samples of local arable soils and potatoes were taken from 138 private subsidence farms (PFs).The iodine content in the studied soils of the private farms of the Bryansk region ranged from 0.11 to 3.5 mg/kg (air-dry weight). The content of iodine in potatoes grown on these soils varied within a considerably wider interval: from 0.002 to 0.119 mg/kg (wet weight), averaging 0.033 mg/kg, which indicates a generally low iodine transfer to this particular product. The data obtained deserve attention when organizing monitoring and carrying out measures for the prevention of iodine deficiency. [ABSTRACT FROM AUTHOR]

Forests occupy approximately 27% of Romania's total surface. Forest soils from Ialomița County were characterized based on a large number of soil analysis obtained during the last 26 years (namely 127 soil profiles and 335 pedogenetic horizons). These soils are characteristic to the field area from the silvosteppe areal and have developed under a humid regime (phaeozem, chernozem, preluvisol, luvisol, fluvisol). Chernozem and cambic phaeozem have a weak alkaline reaction and a B cambic horizon (Bv) resulted from the clay's concentration, while carbonates are concentrated in depth. Fluvisols have a large development in the Danube's meadow, especially in its affluent, namely Ialomiţa River's meadow. The parental material is represented by sands, clay sands and slime. Furthermore, organic matter in humification progress is also present. Luvisols and preluvisols are moderately acid soils in the Ao and Bt horizons, mesobasic in Ao and Bt and with a high cationic exchange capacity. They are also moderately humiferous, well supplied with nitrogen and with a good cationic exchange capacity. [ABSTRACT FROM AUTHOR]

Soil-archeological studies were performed in the area of the ancient Russian settlement Sorokino 1 dating back to the 13th century AD and located in the upper reaches of the Orlik River (Khotynets district, Orel oblast) within the natural zone of deciduous forests. Morphological, physical, and chemical properties of soils associated with the archeological monument and with the background area under the forest were analyzed. Phytolith spectra and the radiocarbon age of soil organic matter were determined in the paleosols of the archeological monument and in the background surface soils. A comparative analysis of the soil features—indicators of the environment—allowed us to determine and characterize the main stages of the formation of soils and landscapes under the influence of climate changes and anthropogenic factors. Climate-related alternation of the phases of steppe and forest development in the study area was revealed. Steppe conditions in the Boreal period of the Holocene were replaced by the spreading of deciduous forests in the Holocene Optimum (Middle Atlantic period). At the end of the Atlantic period, steppe landscapes reappeared in the area, which was reflected in the intensification of the activity of steppe burrowers (mole rats) in the soil profiles. Steppe formation in river valleys during the Medieval Climatic Optimum was replaced by the propagation of forests in the subsequent Little Ice Age. The analysis of phytolith complexes of different ages indicated that the forests growing in the studied area in the Late Holocene included both deciduous and coniferous trees and reflected cooler climatic conditions in comparison with the deciduous forests without conifers of the Atlantic Optimum. In the recent centuries of the active agricultural development, forests have been replaced by arable land and hayfields, which has led to the formation of chernozems in the areas previously occupied by dark gray forest soils (Luvic Greyzemic Phaeozems). [ABSTRACT FROM AUTHOR]

Experimental data on size distribution of micro- and macroaggregates and primary soil particles were obtained by laser diffraction analysis of the samples of humus horizons of the zonal soil sequence (from Retisols to Kastanozems) in European Russia. Both undisturbed native soils and agricultural soils were analyzed. The relationships between the parameters of the size distribution of aggregates, microaggregates, and primary particles were valuated. The parameters of the size distribution (content of the particles and their mean-weight diameter) were compared with data on the contents of water-stable aggregates, organic carbon, nitrogen, phosphorus, potassium, and pH. Size distribution of primary particles in the humus horizons of Endocalcic Chernozems had a bimodal pattern. A positive linear correlation between the contents of microaggregates and organic carbon was found to occur only when the latter exceeded 2–3%. An index of the size distribution of microaggregates—the minimum size of stable microaggregates—was proposed; it can be determined as an intersection point of differential curves of size distribution of microaggregates and primary particles. For this index, a negative correlation with the soil pH was found. It was supposed that the observed correlation reflects the coagulation of soil colloids, when their electric charge is compensated. [ABSTRACT FROM AUTHOR]

On the Cis-Salair Plain with well-drained soils, the statistical dependence of the yield of spring wheat and NDVI on some properties of the plow horizon in eluviated clay-illuvial agrochernozems (Luvic Greyzemic Chernozems) and agro-dark gray soils (Luvic Retic Greyzemic Phaeozems) was studied. In the regression model, the NDVI was shown to be responsible for 85% of the variation in the yield of spring wheat. Using the model and the spatial distribution of NDVI as the cartographic base, the prediction and visualization of the spatial variability of the spring wheat yield was performed. The spring wheat productivity and the NDVI proved to be insignificantly different for the agro-dark gray soils and agrochernozems. The correlation was significant between the yield of spring wheat and the NDVI, on one hand, and the pre-sowing water content (r = 0.52; r = 0.57) and the content of exchangeable potassium (rs = 0.58; rs = 0.61), on the other hand; the correlation with the contents of humus (r = 0.35; r = 0.38), available phosphorus (rs = 0.32; rs = 0.35), and mobile zinc (rs = 0.42; rs = 0.48) was moderate. Relatively high contents of mobile forms of macro- and microelements in soils correlated with higher values of the presowing water content. [ABSTRACT FROM AUTHOR]

To assess the soil quality of Phaeozems and Luvisols from Kujawy region (Kujawy-Pomerania Province, Poland), the soil quality indicators such as: content of organic matter and nutrients, as well as bulk density were used. The soils showed similar inherent properties (soil texture, depth to parent material, type of clay) and management practices (tillage, crop rotation, nutrient application). The following properties were determined: bulk density, grain size composition, exchangeable acidity, concentration of available forms of potassium, phosphorus and magnesium, and the content of total organic carbon (TOC) and nitrogen (Nt). The amounts of dissolved organic carbon (DOC) and dissolved nitrogen (DN) were measured in the solution obtained after extraction with 0.004 M CaCl2. The stock of TOCs, Nts and DOCs, and DNs were calculated. The total organic carbon content in surface horizon of Phaeozems was significant higher (13.9-20.1 g·kg-1) than in Ap horizon of Luvisols (8.3-11.0 g·kg-1), which is a consequence of their origin. The stock of organic carbon in Ap horizon fell within 5.89 to 8.49 kg·m2 in Phaeozems and 3.80 to 4.81 kg·m2 in Luvisols. Although Phaeozems demonstrated a significant higher content of TOC, as compared with Luvisols, the amount of dissolved organic carbon was similar in both soil types, which points to a higher share of DOC in the total organic carbon content in Luvisols (up to 17.5% in Et horizon). The amounts of dissolved organic carbon and dissolved nitrogen and their stock do not depend on the type of soils if the management practices are similar.

Abstract 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. [ABSTRACT FROM AUTHOR]

Temporal changes in soils of forest landscapes of the forest-steppe zone—Haplic Luvisols and Greyzemic Phaeozems—under the impact of Holocene climate changes (natural factor) and long-term cultivation (anthropogenic factor) were studied on level interfluves of the Central Russian Upland. These soils were developed from covering loesslike loam of varying thickness. To study soil evolution under the impact of climate changes, soil chronosequences of archaeological sites—paleosols buried under ramparts of ancient settlements and background surface soils of adjacent areas—were analyzed. The time of the soil burying was determined via the 14C dating of charcoal from thin twigs sampled in the material of ramparts immediately above the surface of buried soils. According to 14C dates, the paleosols were buried in the interval from 2450±40 to 1150±110 BP. Before the Subatlantic period, these paleosols developed under grassland (steppe), which is proved by their properties typical of steppe soils and by the presence of paleokrotovinas—the features created by the burrowing activity of steppe animals (mole rats)—in the studied profiles. The 14C dates of the total organic carbon of humus in the dark gray filling of a paleokrotovina from a Phaeozem buried at the depth of 140–150 cm under the rampart of 1150±110 BP in age ranged from 6080±150 to 2810±60 BP. The evolution of steppe Chernozems into forest Phaeozems and Luvisols took place in the Late Holocene. The anthropogenic evolution of forest Luvisols and Phaeozems under the impact of long-term (more than 150–230 years) plowing was analyzed in the soil agrochronosequences that included background soils under native forest vegetation and their arable analogs with different durations of cultivation. It was concluded that this evolution is directed towards Chernozemic pedogenesis, i.e., it proceeds in the direction opposite to the natural trend of pedogenesis in the Late Holocene. This process takes place despite the traditional practice of limited application of organic fertilizers in arable farming in the studied region. A decrease in the mean residence time (MRT) of total organic carbon (TOC) in the old-arable soils is considered a consequence of the formation and accumulation of fresh humus material in the profiles of cultivated soils—one of the major processes in the transformation of arable forest soils into Chernozems. The accumulation of carbonates and an increase in their 14C age take place in the arable soils in comparison with their forest analogs. In the agrochronosequence from the Polyana site, the 14C age of carbonates at the depth of 170–180 cm reaches 8000±100, 8270±150, and 9150±100 BP under the forest, 100-year-old plowland, and 150-year-old plowland, respectively. This can be explained by the ascending migration of ancient carbonates from the parent material in suspensions. In the analogous Samarino agrochronosequence, the 14C age of carbonates from the depth of 90–100 cm comprised 6500±90, 7150±100, and 12,360±230 BP, respectively. Thus, the studied forest-steppe soils have a polygenetic nature specified by a complicated history of pedogenesis under the impact of both natural (climate-driven forest invasion into steppe) and anthropogenic (deforestation and land plowing) factors. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this paper has been to determine the seasonal changes in the content of dissolved organic matter (DOM) in the soils under agricultural use based on assaying changes in dissolved organic carbon (DOC) and dissolved nitrogen (DNt) as well as determining the factors which can define the DOM in soils.Materials and methods: The research has involved the soils under agricultural use sampled in the Kujawsko-Pomorskie province (Poland). Phaeozems and Luvisols were sampled from the depth of 0-30, 30-60, and 60-100 cm, November 2011 through September 2013, in November, March, May, July, and September. The soil samples were assayed for the grain size composition, pH, dry weight content, content of total organic carbon, and total nitrogen. Dissolved organic matter was extracted with 0.004 mol dm3 CaCl2; in the DOM extracts, the content of dissolved organic carbon (DOC) and dissolved nitrogen (DNt) were assayed. The research results were statistically verified.Results and discussion: It has been demonstrated that in the first year of research, the content of dissolved organic carbon in the soils was changing throughout the year. The highest differences in the content of that carbon fraction occurred across the soil sampled in autumn and the soil sampled in spring. In the second year of research, an inverse dependence was noted. DOC was migrating to deeper layers of the soil profile; yet, the migration got more intensive in summer. The content of dissolved nitrogen was not changing significantly throughout the year. Higher DNt content in the surface layer, in general, resulted in a higher content of dissolved nitrogen in deeper profile layer, which could have been due to leaching of the nutrient deep down the soil profile.Conclusions: The content of dissolved organic carbon was significantly related to the content of total organic carbon and total nitrogen. Significant changes in the content of dissolved forms of nitrogen were reported in the profile of Phaeozems due to mineral fertilization and irrigation. The soils where irrigation and higher nitrogen rates had been applied demonstrated a higher content and share of soluble forms of nitrogen, as compared with the soils non-irrigated and the soils where lower nitrogen rates had been supplied. [ABSTRACT FROM AUTHOR]

The spatial structure of the habitat for plant communities based on soil functions in virgin forest-steppe of the Central Russian Upland is the focus of this study. The objectives include the identification of the leading factors of soil function variety and to determine the spatial heterogeneity of the soil function. A detailed topographic survey was carried out on a key site (35 hectares), 157 soil, and 34 geobotanical descriptions were made. The main factor of soil and plant cover differentiation is the redistribution of soil moisture along the microrelief. Redistributed runoff value was modelled in SIMWE and used as a tool for spatial prediction of soils due to their role in a habitat for plant communities’ functional context. The main methods of the study are the multidimensional scaling and discriminant analysis. We model the composition of plant communities (accuracy is 95%) and Reference Soil Group (accuracy is 88%) due to different soil moisture conditions. There are two stable soil habitat types: mesophytic communities on the Phaeozems (with additional water runoff more than 80 mm) and xerophytic communities on Chernozems (additional runoff less than 55 mm). A transitional type corresponded to xero- mesophytic communities on the Phaeozems with 55–80 mm additional redistributed runoff value. With acceptable accuracy, the habitat for natural plant communities based on soil function model predicts the position of contrastingly different components of biota in relation to their soil moisture requirements within the virgin forest-steppe of the Central Russian Upland.

This study describes and classifies the soils of the foot and toe slopes of the Vukan Mountain, Central Serbia, the contact point of two distinct geomorphological units, with a focus on their spatial distribution and their main soil-forming processes. The Vukan Mountain is formed of Jurassic limestones and dolomites, whereas the foot and toe slopes are of fluviatile-colluvial origin. A total of 42 soil profiles were examined. Soil profile locations were determined with respect to elevation differences, accounting for a set of six profiles for every 5-m elevation increase between 175 and 210 m a.s.l. The area is characterized by the dominance of chernic and mollic topsoil horizons and the major part of the area is covered with Phaeozems. Five Reference Soil Groups were found in a very small area. Eleven soil profiles are Chernic Phaeozems, five are Cambic Phaeozems, and twelve are Rendzic Phaeozems. The central part of the study area is characterized by the accumulation of secondary carbonates and Chernozems were identified. The northern part of the study area is covered with Fluvisols, Calcisols, and Leptic Rendzic Phaeozems, whereas Chernic and Cambic Phaeozems and Eutric Cambisols cover the western part of the study area. The differences in the CaCO 3 content in the gravels, the differences in the gravel content, and the different lateral and vertical distribution of CaCO 3 are strong evidence of surface processes that occurred in the past. The presence of different geological layers and buried horizons suggests fluviatile processes. The spatial distribution of soils is related mainly to parent material occurrence, and colluvial and alluvial processes that occurred in the past. The soil map created in GIS has Reference Soil Group as central unit following Rule 1 for map legend creation, except in the case of Phaeozems, which are present as Phaeozems (Leptic) and Phaeozems (other) following Rule 5. This soil survey with approximately one soil profile per 4 ha has indicated considerable soil heterogeneity in the study area. Detailed surveys are therefore recommended for areas with pronounced heterogeneity of soil-forming factors. [ABSTRACT FROM AUTHOR]

Specific features of the horizontal and vertical distribution of uranium and thorium in soils and parent materials of the Southern Urals within the Bashkortostan Republic have been studied with the use of mass spectrometry with inductively coupled plasma. The dependence of distribution patterns of these elements on the local environmental conditions is shown. A scale for soil evaluation according to the concentrations of uranium and thorium (mg/kg) is suggested: the low level, up to 3; medium, up to 9; high, up to 15; and very high, above 15 mg/kg. On the basis of to this scale, the ecological state of the soils is evaluated, and the schematic geochemical map of the region is compiled. The territory of Bashkortostan is subdivided into two parts according to the contents of radioactive elements in soils: the western part with distinct accumulation of uranium and the eastern part with predominant thorium accumulation. This finding supports the charriage (thrust fault) nature of the fault zone of the Southern Urals. The vertical distribution patterns of uranium and thorium in soils of the region are of the same character. The dependence between the contents of these two elements and rare-earth elements has been established. The results of this study are applied for assessing the ecological state of soils in the region. [ABSTRACT FROM AUTHOR]

The number and taxonomic structure of the yeast complexes were investigated in the full profiles of the soddy-podzolic soil (Central Forest State Nature Biosphere Reserve), dark gray forest soil (Kaluzhskie Zaseki Reserve), and chernozem (Privolzhskaya Forest-Steppe Reserve). In all these soils, the number of yeasts was maximal (10 CFU/g) directly under the litter; it drastically decreased with the depth. However, at the depth of 120-160 cm, the number of yeasts significantly increased in all the soils; their maximum was found in the illuvial horizon of the soddy-podzolic soil. Such a statistically significant increase in the number of yeasts at a considerable depth was found for the first time. Different groups of yeasts were present in the yeast communities of different soils. The species structure of yeast communities changed little in each soil: the same species were isolated both from the soil surface and from the depth of more than 2 m. The results showed that yeasts could be used for soil bioindication on the basis of specific yeast complexes in the profiles of different soil types rather than individual indicative species. [ABSTRACT FROM AUTHOR]

The influence of bioclimatic conditions related to the elevation above sea level on the quantitative and qualitative parameters of humus in mountain soils has been studied. It is shown that changes in the water and temperature conditions with the altitude do not exert significant effect on the humus content in mountain- forest soils, because the total amount of soil organic matter mainly depends on the composition and state of the vegetation cover. The humus content is the highest in meadow soils formed on mountain plateau with excessive moistening, which determines the formation of dense grass cover and the temperature regime favorable for humification. The percentage of C ha in the composition of C org and the optical density of humic acids (HAs) are the qualitative parameters of the soil humus status changing with the altitude. The intensity of humus coloring of the soil depends on the content and optical density of HAs. A comparison of color intensity in the mountainous meadow chernozemlike soils and plain chernozems has shown its significant dependence on the hydrothermic conditions. [ABSTRACT FROM AUTHOR]

The most spread are soils with vertic properties at the territory of Kamennaya Steppe (Voronezh region, Talovsky district) being confined to four landscape positions within 11 different soil combinations derived from clayey or two-layered heavy loam-clayey parent materials. These soils have developed: (A) on bottoms of deep and closed depressions covered by spotted soil combinations in flat watersheds; (B) on some depression bottoms in spotted combinations without solonetzic soils; (C) in different relief elements occupied by chernozemic hydromorphic solonetz complexes and (D) in concave (in long and cross directions) relief elements in the topolithomosaic composition confined to exposed re-deposition products of Dnieper moraine on the slope of Talovaya narrow. Occupying only 0.2% from the total area of agro-forest landscapes, the vertic soils can account for 0.7% to 15% within a separate soil combination and reveal a great diversity. The latter is associated with vertic properties developed together with features of gleying and quasi-gleying, accumulation of calcium carbonates and, on the contrary, clay illuviation against the background of calcium carbonate leaching, solonetz process, salinization, humus formation and the topsoil eluviations. Such a diversity may be adequately reflected both in the soil classification of Russia and in WRB.