Soil cover pattern on the northern macroslope of the Tsagan-Daban Ridge in the Transbaikal region

Regularities of soil distribution in the basin of the Vorovka River on the northern macroslope of the Tsagan-Daban Ridge are discussed, and the grouping of soil cover patterns in this area is suggested. Dissected middle-mountain areas covered by taiga forests are characterized by a combination of predominate soddy podburs with small homogeneous areas of podburs and lithozems. Within the piedmont part of the basin, components of soil combinations are different. The major areas are occupied by sandy soils under dry grassy pine forests; poorly developed soils are formed on recent alluvial and colluvial deposits in the depressions and hollows.     

Genetic specificity and geography of taiga soils in the central part of the Baikal region

A specific feature of the development of automorphic taiga soils in the Baikal region is the lack of correspondence between the weak intensity of the soil chemical weathering and the high intensity of the removal of alkaline-earth elements from the soil profile in the form of suspensions. The loss of the clay fraction affects the water-physical properties of these soils and their temperature regime. The areas of different soil types in the northern and middle taiga zones have been calculated on the basis of soil maps of different scales. It is shown that podburs and acid soddy taiga soils predominate in these zones; the area of podzols, which were previously considered to be the dominant soil type in the middle and southern taiga zones, is smaller.     

Soil cover patterns and land assessment in the Baikal region of Buryatia using the example of the Kabansk district

The soil cover patterns in the Kabansk district (the Baikal region of the Buryat Republic), including the Selenga River delta, are analyzed. A soil map of this area has been developed on a scale of 1 : 500000. Stony organic soils are widespread in the tundra zone. Mountain-meadow soddy soils and tundra podburs (under dwarf pine) are formed at lower heights around lakes and in glacial valleys. Kabansk district includes taiga landscapes on the northern slopes of the Khamar-Daban Ridge with the predominance of podburs, podzols, soddy-taiga soils, and burozems. Agrolandscapes occur in the Nizhneselenginsk meadow-bog and forest-steppe natural region with a predominance of soddy forest, soddy gray forest, meadow, alluvial, meadow-bog, and bog soils. Data on the land evaluation in the agricultural part of the studied region are given.     

A map of the soil cover patterns in the western part of the Transbaikal region (1: 500000 scale)

The results of soil surveys in the Khorinsk district of the Buryat Republic have been generalized on a map of the soil cover patterns on a scale of 1: 500000. The map reflects the soil cover patterns in the zones of mountainous tundra and taiga, mountainous forest-steppes, sand massifs on piedmonts, and plain steppes and dry steppes. The areas of each component of the soil combinations shown on the map have been calculated. In the course of the generalization of large-scale soil maps, information on the genetic types and subtypes of soils has been preserved. The new map adequately displays the real pattern of the soil distribution in the studied area.     

Soils and the soil cover of the taiga zone in the northern Urals (upper reaches of the Pechora River)

The territory in the upper reaches of the Pechora River is characterized by the predominance of Al-Fe-humus and metamorphic soils with gley features developing under the middle taiga fir-spruce forests rather than gley-podzolic soils as had been considered before. Some of the described soil profiles represent intergrades between brown taiga soils (burozems) and gleysols; these soils are absent in the new Russian soil classification system. General regularities of the soil cover are controlled by the geomorphic position of the soils on slopes and by the conditions of ground moistening and lateral soil water flows. The development of modern soil cover patterns is determined by the impact of herbaceous and woody vegetation, bioturbation of the soils by windfalls, the presence of dead tree trunks on the soil surface, and other factors.     

Digital soil map of the Ussuri River basin

On the basis of digital soil, topographic, and geological maps; raster topography model; forestry materials; and literature data, the digital soil map of the Ussuri River basin (24400 km²) was created on a scale of 1: 100000. To digitize the initial paper-based maps and analyze the results, an ESRI ArcGIS Desktop (ArcEditor) v.10.1 (http://www.esri.com) and an open-code SAGA GIS v.2.3 (System for Automated Geoscientific Analyses, http://www.saga-gis.org) were used. The spatial distribution of soil areas on the obtained digital soil map is in agreement with modern cartographic data and the SRTM digital elevation model (SRTM DEM). The regional soil classification developed by G.I. Ivanov was used in the legend to the soil map. The names of soil units were also correlated with the names suggested in the modern Russian soil classification system. The major soil units on the map are at the soil subtypes that reflect the entire vertical spectrum of soils in the south of the Far East of Russia (Primorye region). These are mountainous tundra soils, podzolic soils, brown taiga soils, mountainous brown forest soils, bleached brown soils, meadow-brown soils, meadow gley soils, and floodplain soils). With the help of the spatial analysis function of GIS, the comparison of the particular characteristics of the soil cover with numerical characteristics of the topography, geological composition of catchments, and vegetation cover was performed.     

Coevolution of soils and vegetation in the southern taiga (with the Prioksko-Terrasnyi reserve as an example)

A detailed characterization of the relief, parent materials, soils, woody vegetation, and the links between them is given for a small part of the southern taiga zone in the center of the East European Plain. A methodology for determining the vegetation succession patterns on different soils with the use of the selectivity coefficient K is suggested. This coefficient is defined as the ratio between the frequency of occurrence of the given tree species on a given soil and its average frequency of occurrence within the entire analyzed area (in the area of the reserve). The values of K change from 0.2 to 3.6 and indicate positive (K > 1) and negative (K < 1) feedback relationships between the soils and vegetation. Changes in the frequencies of occurrence of different tree species on different soils that took place over 19 years have also been studied. It is shown that spruce has a tendency for settling on podzols, mixed spruce-oak-lime forests tend to develop on podzolized podburs, and lime and oak trees tend to develop on soddy podburs. Birch stands are most often replaced by spruce and pine stands; aspen stands and a part of the birch stands are replaced by lime and oak stands. The ecological plasticity of pine trees and the long age of this tree species ensure the existence of a long transitional succession stage with the predominance of pine. These regularities are important for predicting the further development of forest vegetation.     

Soils of the subtaiga landscapes on the northern spurs of the Tsagan-Daban Ridge in the Selenga Mountains

The soil cover patterns in the subtaiga landscapes on the northern spurs of the Tsagan-Daban Ridge in the Selenga Mountains have been studied. Gray-humus lithozems and bedrock outcrops are typical of the steep south-facing slopes under herbaceous pine forests. Soddy iron-illuvial podburs are formed under forest vegetation on gentle slopes of northern and western aspects with a thick mantle of loose colluvial deposits. Dark-humus metamorphic soils occur on the slopes of western and northwestern aspects below 700 m a.s.l. under secondary forb-grassy communities that replaced the initial herbaceous pine forests. Windblown hollows (yardangs) are occupied by humus psammozems under steppe pine forests. The morphological and physicochemical characteristics of these soils are discussed in the paper.     

Soils of the northern part of the Subpolar Urals: Morphology, physicochemical properties, and carbon and nitrogen pools

The morphology and physicochemical properties of mountain-tundra and mountain-forest soils of the Subpolar Urals are analyzed. Gleyic humus-illuvial podburs, in combination with humus-illuvial podburs and raw-humus gleyzems, predominate in the mountain-tundra zone; permafrost-affected gleyzems and peat gleyzems with a shallow (30–50 cm) permafrost table are developed on colluvial fans at the foots-lopes. Iron-illuvial podzols, iron-illuvial svetlozems, eluviated burozems, texture-differentiated podzolic soils with a microprofile of a podzol, and gleyed peat-podzolic soils occur in the mountain-forest zone. The organic carbon and nitrogen pools in the soils considerably vary depending on the soil type and local landscape conditions. The organic carbon pool stored in the upper 50 cm of the soil profile varies from 7.7 to 39.3 kg/m² in the mountain-tundra soils and from 6.5 to 11.8 kg/m² in the mountain-forest soils. The corresponding values for the nitrogen pool are 0.4–2.4 and 0.4–0.8 kg/m², respectively.     

Soil cover patterns and land resources in the south of the Selenga mountainous region

Soil cover patterns within the Kyakhta area of pine stands and the Kudarinsk area of dry steppes in the south of the Selenga mountainous region are characterized. The groups of soil combinations are shown on the map developed on a scale of 1: 500000. The areas of particular soils composing the combinations have been calculated. Thus, this small-scale soil map generally preserves information reflected on large- and medium-scale soil maps.     

Soils on hard rocks in the northwest of Russia: Chemical and mineralogical properties,genesis, and classification problems

Soil formation on hard rocks—nepheline syenite, amphibolite, metamorphized gabbro diabase, and their derivatives—was studied in the mountainous tundra and in the northern and middle taiga zones of the Kola Peninsula and Karelia (in the Kivach Reserve). It was found that the soils developing from these rocks could be classified into three groups: (1) petrozems with the O-M profile (the most common variant), (2) podzols and podzolized podburs on the substrates with an admixture of morainic derivatives of acid rocks, and (3) shallow (<5–10 cm) pebbly soils on the substrates without an admixture of allochthonous material (the rarest variant). In soils of the third group, the pedogenic alteration of the mineral matrix does not result in the appearance of phyllosilicates in the fine fractions if these phyllosilicates are initially absent in the rock. In these soils, the protion of the organic matter, and binding of iron released from the weathered silicate minerals into iron-organic complexes) are virtually undifferentiated by the separate soil horizons because of the very low thickness of the soil profiles. These soils have the Oao-BHFao-M profile; it is suggested that they can be classified as leptic podburs. An admixture of morainic material containing phyllosilicate minerals favors a more pronounced differentiation of the modern pedogenic processes by separate soil horizons even in the case of shallow soil profiles; the intense transformation of phyllosilicates takes place in the soils.     

Soils of the Zeya-Bureya interfluve and their rational use

Meadow-chernozemic and dark chernozem-like meadow soils predominate on the Zeya-Bureya interfluve. The soil cover pattern of this interfluve is described in terms of elementary soil areas (ESAs) and soil combinations (SCs). The typification of elementary agricultural areas on the basis of major characteristics of the ESAs and SCs and the ways of their rational management are suggested. It is shown that most of the regional soils require phosphorus fertilizers and liming; agromeliorative and hydromeliorative drainage measures should be implemented on vast areas to improve soil productivity.     

Soils of the Southwestern Part of the Pacific Coast of Russia

The diversity of soils in the southwestern part of the Pacific coast of Russia (Primorie region) is discussed. Overall, 17 soil types belonging to 8 soil orders have been described in this region, and their morphology and properties have been studied. The diversity of plant communities, geomorphic conditions, and parent materials and relatively mild (as compared with other parts of the Far East region of Russia) specify the great variability of soil cover patterns. Low sea terraces are occupied by various peat, organo-accumulative, and gley soils; poorly drained medium-high terraces are the areas of various dark-humus and darkhumus gleyed soils. Typical and gleyic dark-humus podbels, dark-humus, and dark-humus gleyed soils formed on the high sea terraces. Residual elevations are occupied by brown forest (burozemic) soils, including typical burozems, dark-humus burozems, and gleyic dark-humus burozems and by dark-humus podbels. Various alluvial, gleyic gray-humus, and mucky gley soils are developed on riverine plains. On general, darkhumus soils with the high (>10%) humus content predominate; the area of dark-humus podbels us estimated at about 20%, and the area of dark-humus burozems is about 12%. All the soils in this region are specified by increased acidity values. The exchangeable sodium content is often high in the upper soil horizons with maximum values (0.71–1.19 cmol(c)/kg) in the peat gleyzems, peaty dark-humus soils, mucky-gley soils, and eutrophic peat soils of sea terraces. The grouping of the soils with respect to their physicochemical and agrochemical properties is suggested.     

Soil formation in the quarries for limestone and clay production in the Ukhta region

The soils forming on the overgrowing technogenic dumps of quarries for limestone and clay production were investigated in the northern taiga (the Ukhta region). The soils are formed under sparse herbaceous plant communities. In the soils on calcareous technogenic eluvium and clay dumps, the processes of humus formation and accumulation predominate. In the soils of the clay dumps, the leaching of carbonates is expressed to a greater extent than in the soils of the limestone quarries. The nitrogen content of organic matter is low in the soils on the technogenic lime substrates and very low on the clay ones. Fulvic acids predominate in the humus composition. At the stages of the soil restoration studied, the zonal trend of pedogenesis is manifested only in the humus accumulation. The calcareous technogenic eluvium is found to be more favorable for the development of microbial communities as compared to the clay substrates with their small microbial biomass. However, there are no features pointing to the development of zonal soil profiles. This fact attests that, in the first 20–30 years, the soil-forming potential in the northern taiga is insufficient for the initiation of the zonal processes.     

Principles of soil mapping of a megalopolis with St. Petersburg as an example

For the first time, a soil map of St. Petersburg has been developed on a scale of 1 : 50000 using MicroStation V8i software. The legend to this map contains more than 60 mapping units. The classification of urban soils and information on the soil cover patterns are principally new elements of this legend. New concepts of the urbanized soil space and urbopedocombinations have been suggested for soil mapping of urban territories. The typification of urbopedocombinations in St. Petersburg has been performed on the basis of data on the geometry and composition of the polygons of soils and nonsoil formations. The ratio between the areas of soils and nonsoil formations and their spatial distribution patterns have been used to distinguish between six types of the urbanized soil space. The principles of classification of the soils of urban territories have been specified, and a separate order of pedo-allochthonous soils has been suggested for inclusion into the Classification and Diagnostic System of Russian Soils (2004). Six types of pedo-allochthonous soils have been distinguished on the basis of data on their humus and organic horizons and the character of the underlying mineral substrate.     

Morphological-genetic characterization of soils on the Enganepe Ridge

Specific features of the soil formation in the Polar Urals related to the slope aspects, parent rocks, and vegetation are considered using the example of the Enganepe Ridge. Soils of the same type (humus-illuvial podburs and podzolized podburs) are formed under the severe climatic conditions of the mountain tundra belt irrespective of the slope aspect. The main differences in the prevalent soils are manifested in the mountain belt of sparse forests. Under the sparse larch forests on the southeast-facing slope, illuvial-humus-iron podzols predominate. On the south-facing slope under the sparse spruce forests, clay-illuviated illuvialhumus-iron podzols alternate with mucky-dark humus soddy lithozems. Burozems are formed in a few ecological niches. The richness of the parent rocks, along with the southern slope aspect and the transitional-accumulative nutrient transfer, is shown to promote the formation of sparse spruce forests under the climatic conditions of the Polar Urals.     

Dynamics of Soil Properties and Plant Composition during Postagrogenic Evolution in Different Bioclimatic Zones

The postagrogenic dynamics of acidity and some parameters of humus status have been studied in relation to the restoration of zonal vegetation in southern taiga (podzolic and soddy-podzolic soils (Retisols)), coniferous-broadleaved (subtaiga) forest (gray forest soil (Luvic Phaeozem)), and forest-steppe (gray forest soil (Haplic Phaeozem)) subzones. The most significant transformation of the studied properties of soils under changing vegetation has been revealed for poor sandy soils of southern taiga. The degree of changes in the content and stocks of organic carbon, the enrichment of humus in nitrogen, and acidity in the 0- to 20-cm soil layer during the postagrogenic evolution decreases from north to south. The adequate reflection of soil physicochemical properties in changes of plant cover is determined by the climatic zone and the land use pattern. A correlation between the changes in the soil acidity and the portion of acidophilic species in the plant cover is revealed for the southern taiga subzone. A positive relationship is found between the content of organic carbon and the share of species preferring humus-rich soils in the forest-steppe zone.     

Soil map of the Russian Arctic on a 1 : 1 M scale: Contents and compilation methods

A new soil map of the Russian Arctic on a scale of 1 : 1 M shows the soil cover in the north of Eurasia and on the islands of the Arctic Ocean to the north of 68° N. This map has been developed in a geoinformation system in the vector format with the wide use of remote sensing data. The delineated soil polygons show dominant and accompanying soils and the structure of soil cover patterns with indication of soil associations and soil complexes, the character of parent materials, and the topographic conditions. The map of the soil-geographic zoning of the Russian Arctic developed on the basis of the soil map differs from its earlier analogues in a greater degree of detail. The soil map of the Russian Arctic on a scale of 1 : 1 M displays the most detailed information on the soil cover patterns and can be used for solving various problems related to the exploration and development of this territory. Soil names from the new classification system of Russian soils [10] have been introduced into the legend of the map. New soil information and the use of remote sensing data have made it possible to enlarge the number of soil polygons shown on the map and to correct their boundaries in comparison with previous soil maps of the Russian Arctic.     

Soils of the Lena-Angara Plateau in the area of the Kovykta gas condensate field

It is shown that soil-forming rocks—red calcareous silicate Lower Ordovician and Upper Cambrian deposits—play the leading role in the formation of unique long lastingly frozen mountainous taiga soils of Central Siberia. The functional role of the litter horizon forming under dark coniferous forests is analyzed. This horizon is sensitive to the bioclimatic factor. The genetic specificity of the predominating prepodzolic soils, podburs, soddy burozems, and soddy-calcareous soils and of the locally forming shallow pink-colored podzols is shown.