Assessment of soil quality in different ecosystems (with soils of Podolsk and Serpukhov districts of Moscow oblast as examples)

The values of the soil-ecological index and microbiological parameters (the carbon of microbial biomass C_mic, its ratio to the total organic carbon C_mic/C_org, and basal respiration) were determined for the soddy-podzolic, soddy-gley, bog-podzolic, meadow alluvial, and gray forest soils under different land uses (forest, fallow, cropland, and urban areas) in the Podolsk and Serpukhov districts of Moscow oblast (237 and 45 sampling points, respectively). The soil sampling from the upper 10 cm (without the litter horizon) was performed in September and October. To calculate the soil-ecological index, both soil (physicochemical and agrochemical) and climatic characteristics were taken into account. Its values for fallow, cropland, and urban ecosystems averaged 70.2, 72.8, and 64.2 points (n = 90, 17, and 24, respectively). For the soils of forest ecosystems, the average value of the soil-ecological index was lower (54.4; n = 151). At the same time, the micro-biological characteristics of the studied forest soils were generally higher than those in the soils of fallow, cropland, and urban ecosystems. In this context, to estimate the soil quality in different ecosystems on the basis of the soil-ecological index, the use of a correction coefficient for the biological properties of the soils (the C_mic content) was suggested. The ecological substantiation of this approach for assessing the quality of soils in different ecosystems is presented in the paper.     

Features of the soil cover of the Vetluga-Unzhensk interfluvial area (Northeast of the Kostroma oblast)

This paper reveals the features of the soil cover of the territory of the Vetluga-Unzhensk interfluvial area, which is adjacent to the northern part of Uvaly, where contrasting combinations of alpha-humic and organo-accumulative soils are widespread. This is due to abruption of the clayey rocks of the Triassic age on the background of fluvioglacial sand sediments of the Dnieper glaciation, which is due to the complicated history of the formation of the relief of the characterized territory.     

The influence of recreation on the city forest landscape (based on the example of the Losinyi Ostrov National Park, Moscow)

The recreational load on Losinyi Ostrov amenity forest was estimated. It was shown that an increase in the human impact leads to deterioration of the ecological condition of trees and their growing conditions. The changes in soil properties are complex and observed only in the layer of 0–20 cm. To improve the reliability of conclusions about these changes, it is recommended that their weighted average values be used (which take into account the area occupied by the network of footpaths and soil properties on them). The bulk density, electrical conductivity, and pH_water of soils have a considerable impact on the ecological condition of lime trees.     

The spatial-temporal dynamics of the structure of bacterial complexes on the Medvenka River floodplain (Moscow oblast)

The distribution of bacteria in separate tiers of the floodplain ecosystem was studied by the methods of direct luminescent microscopy and inoculation onto agar media. The maximum concentration of bacteria was determined in the litter horizon; the bacterial population gradually decreased in the phylloplane and in the soil horizons. The taxonomic structure of the bacterial complexes changed in the vertical direction (in separate tiers) and from season to season. The effect of the floodplain process was seen in the specific composition of bacterial communities in the lower soil horizons; the latter were enriched in the bacterial forms derived from the flood water (spirilla, slipping bacteria, and coryneform bacteria).     

Biomass and respiration activity of soil microorganisms in anthropogenically transformed ecosystems (Moscow region)

In the forest, meadow, arable, and urban ecosystems (recreational, residential, and industrial zones) of Sergiev Posad, Shatura, Serpukhov, and Serebryanye Prudy districts of Moscow region, spatially separated sites (3–5 points per site) have been randomly selected and soil samples have been taken from the 0–10 (plant litter excluded) and 10- to 150-cm layers (a total of 201 samples have been taken). In the samples, the microbial biomass carbon (C_mic), the rate of the basal (microbial) respiration (BR), and the physical parameters (the particle size distribution (PSD), organic carbon (C_org), pH, heavy metals, and nutrients (NPK)) have been determined. High spatial variability has been revealed for C_mic and BR in all the ecosystems and the functional zones of the studied districts, and a clear tendency of a decrease in these parameters has been shown in the arable soils (by 1.4–3.2 times) and the industrial zone (by 1.7–3.3 times) compared to the natural analogues and other corresponding functional zones. It has been shown that the spatial distribution of the microbiological parameters is significantly (p ≤ 0.05) affected by the physicochemical properties of the soil (C_mic by the PSD and PSD × C_org; BR by the pH and pH × NPK; contributions of 40 and 63%, respectively), as well as by the type of ecosystem and the region of study (the contribution of the sum of these factors to the C_mic and BR was 56 and 67%, respectively). A tendency toward the deterioration of the functioning of the microbial community under the anthropogenic transformation of the soil has been shown. The contribution of the urban soils as a potential source of CO₂ emission to the atmosphere has been calculated and discussed.     

Dynamics of denitrification and ammonification activities in the abandoned and intensely cultivated gray forest soils (Tula oblast)

The results of experimental study of daily dynamics of denitrification activity and the activity and population density of ammonifiers in the abandoned (converted to long-term fallow) and intensely cultivated gray forest soils (Luvic Retic Greyzemic Phaeozems (Aric)) are discussed. The potential denitrification activity in the arable soil is higher than that in the fallow soil, whereas the actual denitrification activity in the arable soil is lower. Data on the dynamics of ammonification do not show reliable differences between the activities of ammonifiers in the arable and fallow soils, though the number of ammonifying bacteria is considerably higher in the arable soil. Differences in daily dynamics of the numbers of ammonifiers in the fallow and arable soils are shown.     

Carbon dioxide,methane, and nitrous oxide fluxes in soil catena across the right bank of the Oka River (Moscow oblast)

The flux rates of carbon dioxide, methane, and nitrous oxide in the soils on autonomous, transitional, transitional-accumulative, and accumulative positions of a catena on the Oka River’s right bank (Moscow oblast) were assessed using the chamber method. The lowest rate of C-CO₂ emission (18.8–29.8 mg/m² per hour) was found for the gray forest soil in the autonomous position, and the highest rate (52.4–66.1 mg/m² per hour) was found for the alluvial meadow soil of the accumulative landscape. In the summer, the uptake of methane from the atmosphere exceeded its release from the soil at all the points of the catena (9–38 μg/m² per hour). The highest rate of the C-CH₄ uptake was observed for the soil in the transitional position. In the fall, the soils in the autonomous, transitional, and transitional-accumulative positions served as a sink of C-CH₄, and the soil of the accumulative position was a source of methane emission. The rate of the N-N₂O emission from the catena soils increased when going from the autonomous position to the accumulative one (0.41–11.2 μg/m² per hour). The spatial variation of the C-CO₂, C-CH₄, and N-N₂O fluxes within the catena was 33, 172, and 138%, respectively. The upper (0- to 10-cm) soil layer made the major contribution to the emission of carbon dioxide. This soil layer was characterized by its C-CH₄ uptake, and the emission of methane was typical for the deeper (0- to 20-cm) layer. The layers deeper than 10 and 20 cm emitted more N-N₂O than the surface layer.     

Long-term dynamics of the anthropogenic salinization of soils in Moscow (by the example of the Eastern district)

The long-term (1989–2010) and seasonal dynamics of the anthropogenic salinization of soils related to the use of deicing mixtures in the Eastern Administrative District of Moscow were examined. Data on the chemical composition of deicing mixtures and on the contents of soluble salts in the snowmelt and in the soil profiles of different functional zones were analyzed. The maps of soil salinization were compiled for 1989, 2005, and 2010; on their basis, the resulting map of the degree of soil degradation was developed. The areas with abnormal concentration of salts in the soils expanded during the study period (21 yrs), and the average content of salts in such areas increased by 3.2 times. The maximum total content of salts was found in the spring season in the soils along major highways.     

Changes in the pattern of land use and its impact on the soils and soil cover of the Tushinskii and Pokrovskoe-Streshnevo forest parks of Moscow

The history of transformation of soils and soil cover in the Tushinskii and Pokrovskoe-Streshnevo forest parks of Moscow is investigated. The peculiarities of the influence of anthropogenic activities on the soil cover and soils are examined with the use of maps and textual materials for a period of more than four centuries. The historical stages of anthropogenic disturbance are established, and different ways of anthropogenic transformation of the soil profiles are described.     

Multiyear dynamics and factors of accumulation of benzo(a)pyrene in urban soils (on the example of the Eastern Administrative Okrug,Moscow)

Multiyear data obtained from a survey of benzo(a)pyrene (BP) in the soils of the Eastern Administrative Okrug (prefecture) of Moscow have shown that, over the period from 1990 to 2006, its concentration increased from 492 to 645 ng/g, exceeding the background value by 145 to 190 times. Two stable and strongly contrasting anomalies of BP have been identified as a result of mapping its distribution across topsoil horizons. The multiyear BP dynamics is reflected on the map of its annual increase in concentration. The intensity of soil contamination by this compound is caused by type of land use and by their salinity level. The average BP concentration in the okrug’s soils amounted to 32.2 maximum permissible concentration (MPC). Soils with levels of contamination deemed extremely dangerous or dangerous are predominant, and their area in 2006 reached 96% of the total territory covered by the survey.     

Spatial variability in the carbon of microbial biomass and microbial respiration in soils of the south of Moscow oblast

Soil samples from the upper 10-cm-thick layer of the humus horizon (without forest litter) were taken in Podol’sk and Serpukhov districts (1130 and 1080 km², respectively) of Moscow oblast. At each sampling site, ecosystem (forest, plowland, or fallow), soil (soddy-podzolic, soddy-gley, bog-podzolic, meadow alluvial, gray forest, and anthropogenically transformed soils of lawns and industrial zones), predominant vegetation, and topography (floodplain and low, medium, and upper parts of watersheds) were determined. The carbon content of the microbial biomass (C_mic) was determined by the method of substrate-induced respiration; we also determined the rate of basal (microbial) respiration (BR) and the organic carbon content, pH, and particle-size distribution. Overall, 237 samples from Serpukhov district and 45 samples from Podol’sk district were analyzed. The BR/C_mic ratios (respiration quotient qCO₂) and C_mic/C_org ratios were calculated. The C_mic content in the soils ranged from 43 to 1394 μg C/kg; the BR varied from 0.06 to 25 μg CO₂-C/g per h, qCO₂, from 0.34 to 6.52 μg CO₂-C/mg C_mic per h; and the C_mic/C_org ratio, from 0.19 to 10.65%. It was found that the most significant factors affecting the variability of the C_mic and BR are the parameters of ecosystem (50% and 80%, respectively) and soil (30% and 9%, respectively). The most significant variability of these indices was found in forest soils; it was mainly controlled by the soil texture (33 and 23%) and the C_org content (19 and 24%). The C_mic parameter made it possible to differentiate the soils of the territory for the purposes of their evaluation, monitoring, and biological assessment more clearly than the BR value and the soil chemical characteristics.     

Input and behavior of polycyclic aromatic hydrocarbons in arable,fallow, and forest soils of the taiga zone (Tver oblast)

Contents of 11 most prevalent polycyclic aromatic hydrocarbons (PAHs) in snow and soils of arable, fallow, and forest areas significantly remote from impact technogenic sources of polyarenes have been examined in the Torzhok district of Tver oblast. From the analysis of snow samples, the volumes and composition of PAHs coming from the atmosphere onto the areas of different land use have been determined. Light hydrocarbons prevail in PAHs. They make up 65–70% of total PAHs; their share in soils reaches almost 95%. An increase in the content of PAHs is revealed in fallow soils compared to arable and afforested areas. A direct relationship is revealed between the lateral distribution of total PAHs and the content of organic carbon. The distribution of total PAHs is surface-accumulative in forest soils, mainly uniform in arable soils, and deepaccumulative in fallow soils. PAH groups characterized by similar radial distributions and ratios between their reserves in snow and soils are distinguished: (1) fluorene and phenanthrene, (2) biphenyl and naphthalene, (3) benzo(a)anthracene, chrysene, perylene, and benzo[a]pyrene, and (4) anthracene and benzo[ghi]pyrene.     

Agrogenic evolution of automorphic chernozems in the forest-steppe zone (Belgorod oblast)

Agrochronosequences of chernozems with different periods of their use in rainfed farming with application of traditional technologies have been studied in a typical forest-steppe area in Belgorod oblast. Certain stages in the development of these soils during more than two centuries of their agricultural use have been identified. These stages are related to changes in the intensity and direction of soil forming processes, such as soil compaction, soil aggregation, dehumification of the upper horizons, calcification of the soil profiles, argillization, etc. A significant impact on the soil changes during the agrogenic evolution of chernozems is exerted by the digging activity of burrowers, which is especially pronounced in the old-arable chernozems.     

Artificial soil-like bodies of a river valley and their evolution in an urban environment (Based on the example of the Moscow River valley)

Technogenic soil-like bodies and raw soils on technogenic sediments in the valley of the Moscow River in the city territory were investigated. Soil destruction and the accumulation of techogenic sediments, as well as their remediation, result in the formation of soil-like bodies called replantozems. Spontaneous overgrowth and the formation of raw soils that gradually evolve into mature urban soils result in soils called urbanozems. It is shown that the best foundation for replantozems in river valleys is in situ alluvium with relatively favorable physical and physical-chemical properties.     

Mercury in soils of the agro-industrial zone of Zima city (Irkutsk oblast)

Data on mercury concentrations in soils of the agro-industrial zone of Zima city in Irkutsk oblast are discussed. It is shown that mercury concentrations in the plow horizon of studied soils exceed background values. The distribution pattern of mercury in soils of the investigated area is characterized. The revealed mercury anomalies are allocated to the industrial zone of the Sayanskkhimprom plant. The combined analysis of data on mercury concentrations in the plow and subplow horizons and on the chemical composition of snow indicates that mercury enters the soil mainly with atmospheric precipitation and is present there in the adsorbed form. The correlation analysis indicates that the local thermal power station plays a significant role as the source of mercury emission to the atmosphere. Close relationships between mercury concentrations and concentrations of mobile forms of elements attest to the presence of mobile organomineral mercury compounds in the studied soils.     

Late pleistocene paleosol sequences as an instrument for the local paleographic reconstruction of the Kostenki 14 key section (Voronezh oblast) as an example

A sequence of five paleosol units (with seven individual paleosol profiles) buried in the Late Pleistocene (20–40 ka) deposits was studied at the Kostenki 14 (K14) key section in Voronezh oblast with the use of a set of morphological, physicochemical, and instrumental methods. The upper-lying paleosols differed from the lower-lying paleosols in the less pronounced gley features, stronger aggregation of the soil material, more significant accumulation of carbonates, and higher percentage of calcium humates and fulvates. These features attested to the higher aridity of the paleoclimate and the development of the upper-lying paleosols under grassy vegetation. Within the studied paleosol sequence, the most developed profiles were typical of the soils that formed 27–32 ka ago during the Bryansk interstadial. The good aggregation, the presence of features left by the soil fauna activity, the high magnetic susceptibility, and the morphology of the secondary carbonates in the studied paleosols suggest that they were formed under meadow-steppe vegetation in well-drained positions and resembled modern cryoarid soils.     

Effect of individual trees on the pH and the content of heavy metals in forest litters upon industrial contamination

The influence of individual spruce and birch trees on the distribution of heavy metals (Cu, Pb, Cd, and Zn) and hydrogen ions in the forest litter is considered in a territory subjected to long-term industrial pollution by emissions of the Ural copper smelter (town of Revda, Sverdlovsk oblast, southern taiga). In the background territory, the content of the elements regularly decreases from the tree trunks to the canopy gaps, whereas, in the contaminated territory, this relationship is either not traced at all (for the metal concentrations) or more weakly pronounced (for the metal reserves and pH values). The influence of trees on the spatial distribution of metals in the litter is specific for various elements and differs in coniferous and deciduous biotopes.     

Soil cover patterns in the southern part of the Sikhote Alin Range (using the example of the Ussuri Nature Reserve)

The soil cover of the Ussuri Nature Reserve in the southern part of the Sikhote Alin Range is described. The geographic regularities of the soil distribution within the territory of the reserve are analyzed, and the major types of soil cover patterns at different levels of their organization are characterized.     

Organizing the ecological monitoring of soils as a constituent part of the state land monitoring and its first results (using the example of Orenburg oblast)

This paper suggests the model for organizing the soil control within the framework of state ecological land monitoring carried out in Russia. Methodical approaches to forming the network of observation areas are expounded. The first results speak for the significant differently directed changes in the properties of soils in Orenburg oblast for the last several decades that are related with erosive processes and transformation of the main physical properties and organic matter.     

Mobile aluminum compounds in soils of the southern taiga (soils of the central forest reserve as an example)

The profile distributions of aluminum extracted by the Tamm and Bascomb reagents and of the exchangeable aluminum were studied in soils of automorphic, transitive, and accumulative positions in the landscapes of the southern taiga. In the mineral horizons of the gleyic peaty-podzolic soils developed on poorly drained flat surfaces and in the floodplain soils, the distribution of oxalate- and pyrophosphate-soluble aluminum has a strongly pronounced accumulative character. In the podzolic soils of the automorphic positions and slopes, an eluvial-illuvial distribution was characteristic with the maximal aluminum content in the podzolic horizons. The strong differentiation of the upper part of the profile in the automorphic podzolic soils in terms of the Al content in the Tamm and Bascomb extracts is mainly related to an increase of the pedogenic chlorite content upon the transition from the AE to the E horizon. In the podzolic horizons of these soils, aluminum can accumulate in the form of proto-imogolite structures. The exchangeable aluminum displays an accumulative type of distribution. On the basis of calculating the reserves of the different aluminum compounds, two main accumulative zones for the mobile compounds of this element were recorded in the soils of the landscapes studied: the E horizon in the automorphic podzolic soils, where Al accumulates as soil chlorite or, probably, as proto-imogolite, and the A1 horizon of the floodplain soils, where Al accumulates in aluminoorganic complexes.