Automorphic Soils Research Articles

Saline soils of arid territories of the southern aral sea region and methods of study for monitoring

The article deals with the issues of soil salinization in the arid territories of the Southern Aral Sea region. In irrigated soils, there is a fairly even distribution of nitrates along the soil profile. The development of secondary salinization in the region can be considered as one of the existing problems that arose as a result of the widespread development of irrigation, which determined the transfer of automorphic soils. This issue requires some elaboration of new approaches to the development of irrigation in the region.

Climatogenic Restrictions of Arid Forestry

The creation of protective forests is especially difficult in arid regions of Russia, and global warming can further affect their ability to persist. In this study climatogenic changes in forest growing conditions are examined in the Northern Caspian region, taking into account that the functioning of forest stands is limited on historically treeless lands: authomorphic meliorated solonetz soils and calcisoles (by the extra moisture of winter snowfalls and the humidity levels during the vegetational period), as well as intrazonal hydromorphic gleyic kastanozems of the local relief depressions (by the inexhaustibility of freshwater lenses in salty subterranean waters based on its periodic resupply by the spring surface flow every 2–4 years). For forest stands established on automorphic soils, a prolonged period of annual draughts and mild winters with little snow deposit in forest lands has proven to be the most dangerous. During such periods, the large-scale death of trees is observed and many forest stands are ruined. For forest stands on hydromorphic soils, such periods prove to be just as dangerous because of the 15-year-long absence of spring surface flow. Such a climatogenic scenario of long-termed deterioration of forest growing conditions in the Northern Caspian region is similar to the southernmost regions of Russia that are currently totally unable to sustain forests, with unstable snow cover and frequent draughts.

Анализ почвенных ресурсов лесов Северо-Восточного Подмосковья на основе геоинформационных технологий

The results of processing and analysis of spatial and temporal information about soils and forest stands on geoinformation technologies are presented. Spatial analysis of combined soil and forestry data showed that the most productive plantings were confined to sod-podzolic automorphic soils. In the main coniferous forest-forming species, such as European spruce and pine, when signs of hydromorphism appear, productivity significantly decreases. Among the studied plantings, the lowest-yielding ones are formed on swamp-podzolic soils. Retrospective analysis revealed a noticeable improvement in productivity and breed composition that occurred in the late 1970s and early 1980s. The assessment of the current situation shows that there is a certain reserve for increasing the productivity of existing forest stands, associated with a more effective use of the natural fertility of forest soils.

Effect of hydrogels on moisture storage of irrigated automorphic soils in Uzbekistan

An experimental study on the development of water-conserving irrigation technology with the use of super swelling hydrogels synthesized out of local raw material has been conducted for three years under the condition of arid automorphic soils of western Uzbekistan. The development of new and affordable water-conserving technologies is critical for the sustainable development of irrigated agriculture in arid zones that severely affected by growing water scarcity. The experiments were aimed at determining the properties of hydrogels, establishing quantitative indicators of the water-holding ability of automorphic soils depending on the methods, norms, and time of application of highly swellable polymer hydrogels under conditions of cotton cultivation. The experiments were conducted under conditions of the irrigated by lifted water automorphic soils and cultivation of the Andijan-35 cotton variety. Results of the study show that use of highly swellable polymer hydrogels with a norm of 50 kg/ha under traditional agrotechnology conditions in conditions of automorphic soils based on improved traditional furrow irrigation technology allows reducing water consumption for irrigation by 15-17% in the first year, by 12-14% in the second year and by 9-11% in the third year of experiments. Due to the longer duration of moisture conservation in the soil, the period between irrigations is extended by 10-12 days, the number of irrigations is reduced.

Растительность класса Loiseleurio procumbentis–Vaccinietea Eggler ex Schubert 1960 в восточноевропейских тундрах

Растительность класса Loiseleurio procumbentis–Vaccinietea Eggler ex Schubert 1960 в восточноевропейских тундрах

The problem of salinization activation in soils of the south of Eastern Siberia and Mongolia in connection with climate aridization

The influence of climate aridization on soil salinity in the basins of the south of Eastern Siberia and Mongolia is considered in the article. The data characterizing the climate aridity of the basins of the south of Eastern Siberia over 50 years are analyzed. In the south of Eastern Siberia from 1955 to 2015, the increase in air temperature was higher than in the whole world. In the basins of Tuva, the increase in air temperature was 2.5–3.7 о С ; in the Minusinsk depression – 1.7–2.8 о С , in the basins of Buryatia – 1.5–1.8 о С ; the coefficient of determination for moving averages over 20 years (R 2 ) was 0.9–0.95, the changes are significant – Student's criterion 19–35. Changes in the aridity coefficient were in the range of 0.02–0.14; according to the Student criterion, they were significant (t = 7.4 – -22), while a decrease in aridization was observed in the Minusinsk depression and its growth in other regions. Thus, in general, for the studied regions, the multidirectionality of the processes of climate aridization has been ascertained. In the Minusinsk depression, despite a slight decrease in aridization, category changes (according to the classification of Lobova et al., 1977) did not occur during this period, the territory remained in the arid and subarid categories. Despite the increase in climate aridization in the basins of Tuva and Buryatia, most of them also did not show a tendency to more arid category. Nevertheless, in a number of hollows in the south of Eastern Siberia, an increase in aridization with a transition to a more arid category was observed. This applies to the Eravnensky and Barguzinsky basins of Buryatia, which switched from weakly arid to subarid, as well as to the Ubsunur basin of Tuva, which turned from arid to strongly arid. For the basins of the south of Eastern Siberia, where climate aridization was recorded, the question arose about the possible activation of the process of soil salinization. To solve this problem, materials were collected on soil salinity in the arid regions of Mongolia. It was found that an increase in climate aridity even in the extreme arid deserts of the Gobi, where parent rocks are not saline, under automorphic conditions, the soil is practically not saline (the amount of salts does not exceed 0.1%). In areas where saline Cretaceous-Paleogene red sediments are spread, automorphic soils are saline, and the amount of salts may exceed 2.5%. Thus, in extremely arid climatic conditions, salinization of automorphic soils can range from non-saline to highly saline. Under the hydromorphic conditions of the basins of the south of Eastern Siberia, as well as in Mongolia, climate aridization inevitably leads to an intensification of the salt accumulation process, therefore, in the basins of Tuva and Buryatia experiencing climate aridization, a process of soil salinization in hydromorphic landscapes should be expected.

Assessment of Organic Carbon Stocks in Forest Soils on a Regional Scale

Results of the comparison of organic carbon stocks in the automorphic and semihydromorphic forest soils are discussed. The database includes information on 289 soil profiles in the forest zone of European Russia. On the average, the total organic carbon pool (including forest litter) in semihydromorphic soils is three times higher than that in automorphic soils. The difference decreases with an increase in the thickness of the considered soil layer from 3.2 times for the layer of 0–30 cm to 2.6 times for the layer of 0–100 cm. The greatest difference in carbon stocks is noted for the organic horizons; in semihydromorphic soils, the carbon storage in them averages 73 ± 8.2 t C/ha; in automorphic soils, it is seven times smaller. The neglect of the contribution of semihydromorphic soils results in underestimation of the total soil organic carbon stock of the region. The degree of underestimation depends on the soil cover pattern of particular areas and on the thickness of the considered soil layer. Calculations made for Karelia show that the underestimation of organic carbon stocks in various landscapes ranges from 10 to 40%. For the total area of this republic, it is estimated at 22, 19, and 13% for the soil layers of 0–30, 0–50, and 0–100 cm, respectively. A comparative analysis of known pedotransfer functions for calculating soil bulk density shows that the best results (RMSE = 0.15; R2 = 0.36) for mineral horizons of forest soils in European Russia are provided by the pedotransfer function suggested by O.V. Chestnykh and D.G. Zamolodchikov.

Technogenic Radionuclides in Soils and Plants of Terrestrial Ecosystems in the Zone of Impact from Nuclear Enterprises

Two closely located major sources of radioactive contamination are operating in the Middle Urals: the Beloyarsk Nuclear Power Plant (BNPP) and Institute of Reactor Materials (IRM). The contamination density of automorphic soils with 239,240Pu is at the global background level, and that with 90Sr and 137Cs, at the level of regional background formed by radionuclides of different genesis deposited from the atmosphere. The front of radioactive contamination has shifted to deeper parts of the soil profile during the past 35 years. Based on the results of our research, the area of deposition of the BNPP and IRM emission plume has been delimited for the first time. The contribution of these sources to its contamination with 137Cs reaches 2.7 kBq/m2. Agreggated transfer coefficients for plants in the BNPP zone are higher than in the East Ural Radioactive Trace, where 90Sr and 137Cs contamination levels are three to four orders of magnitude higher than the background levels. These coefficients depend on the properties of radionuclides and taxonomic identity of plants and decrease with time. This temporal trend is explained by decrease in atmospheric fallout, vertical migration of radionuclides, and increasingly tight 137Cs fixation in soils.

Geochemical features of soils in an undulating glaciolacustrine sandy plain in the middle taiga subzone of Karelia

The geochemically conjugate series of soils (Albic Podzol – Albic Podzol Gleyc – Hystosol) formed on an undulating glaciolacustrine plain in the middle taiga of Karelia was investigated. Surveys for redox conditions showed them to vary from oxidizing in automorphic soils to reducing in soils occupying accumulation-favoring locations. The geochemical coefficients descriptive of the features of accumulation and directions of migration in the studied soils were calculated and analyzed. The distribution of silicic acid and a majority of sesquioxides inside the profile of the studied soils is typical of podzols. The podzolic horizons of the soils occupying interstitial positions have a faster outmigration of elements than in automorphic soils, while their Al-Fe-humic horizons accumulate aluminum, iron, titanium and phosphorus. All the soils are deficient in a majority of microelements as compared to their background levels; very low concentrations were determined for nickel, cobalt and manganese. The content of copper and sometimes zinc is at the background level. The distribution of the studied elements across the soil profile follows the accumulation-eluviation-illuviation pattern, but the scope of variation in the migration of elements varies among topographic positions. In well-drained locations microelements are quite monotonously distributed through the lower part of the soil profile, while soils in transitional landscapes have a higher differentiation of microelements. The differentiation of the catena through lateral migration is of the transient eluviation type, i.e. soils in lower-lying positions are poorer in the studied elements than soils in automorphic positions. This pattern is due to the natural characteristics of the area: low surface slope, homogeneous sandy parent material, low humus content in soil.

Ecological and floristic features of pioner grass vegetation on automorphic sandy soils as the recovery phase of pine forests in Southern Nechernozemye of Russia

Ecological and floristic features of pioner grass vegetation on automorphic sandy soils as the recovery phase of pine forests in Southern Nechernozemye of Russia

Earthworm Populations (Oligochaeta, Lumbricidae) in the Basin of the Middle Reaches of the Bol’shaya Laba River (Northwestern Caucasus, Buffer Zone of Caucasian Nature Reserve)

The species composition and structure of the population of earthworms in the forest and meadow formations in the basin of the middle reaches of the Bol’shaya Laba River are studied for the first time. The species of the Crimea and Caucasus are unusually rare. The erosion topography in combination with significant precipitation results in increased heterogeneity of habitats and in the formation of specific taxocenoses with respect to a hydromorphic or automorphic soil regime. The Crimean–Caucasian subendemic Dendrobaena schmidti, which is the dominant on the northern macroslope of the Great Caucasus, is replaced in automorphic soils by the Easteuro-Asian D. tellermanica, a nemoral-steppe parthenogenetic species, which is well-adapted to a high-amplitude regime of temperature and humidity. Hydrophilic and non-frost-hardy species become numerous in hydromorphic soils. The relationship between the structure of earthworm populations and the soil water regime is illustrated well by the abundance ratio of morpho-ecological forms, among which no anecic are registered. The necessity to protect middle-mountain ecosystems of the northwestern Caucasus as a refugium of Mediterranean earthworm species is shown.

Soil acid-base buffering in the step agriculture lands

Modern studies of chernozem soils in the northwestern Black Sea region have shown intense dehumification due to disruption of biogeochemical cycles caused by anthropogenic removal of organic matter and associated biophile elements. At former time, the humus zoning was typical for southern chernozems and now we noted the smoothing of this zoning. Acid-base buffering has a significant role in counteracting degradation processes, the buffering parameters could be integral indicators of soil chemicals balance. We studied the automorphic soils (arable chernozems) of the northwestern Black Sea region, their humus state, particle size distribution, and acid-base buffering parameters. We studied ordinary modal and micellar-carbonate chernozems on arable land and 40-year-old fallows, southern chernozems removed from irrigation 15 years ago and southern carbonate chernozems of the second floodplain terrace of the Danube River. We determined the neutralization index, degree of buffering capacity in the acid and alkaline ranges, equilibrium coefficient, and sodium absorption ratio to characterize the acid-base buffering. The studied soils belong to stable buffer agriculture lands by their acid-base buffer ability. We determined that soils have the parameters of chernozem type: low humus content, humate and humate-fulvate type of humus, average content of insoluble residue, high degree of humification, heavy-medium loam particle size distribution, and neutral soil solution. The acid-base buffer capacity is characterized by average values, the buffer capacity in the acid interval increases with depth, while decreases in the alkaline interval. We revealed a significant correlation between the ability to counteract the acid load and the content of physical clay. We believe that the agricultural use of southern chernozems leads to a decrease in soil resistance to acidification.

ЗАКОНОМІРНОСТІ ПОШИРЕННЯ ТА ЗАГАЛЬНІ МОРФОЛОГІЧНІ ОСОБЛИВОСТІ СОЛОНЦІВ МЕЖИРІЧЧЯ ДНІПРО-МОЛОЧНА

The traditional approach to the separation of the dry steppe’s solonetz in the most common schemes of classification of Ukraine’s soils is dominated by three types: salt-chestnut-meadow, meadow-chestnut and chestnut. However, the specificity of formation and the possible morphological differences of solonetz of lowlands (pody) and similar reductions, which are quite common within the boundaries of the country between the rivers of Dnipro-Molochna haven’t been taken into account in these schemes. The investigated chestnut-meadow solonetz belong to hydromorphous soils. They have been formed on the territory of the country between the rivers within the flat low-lying coastal shores and various relief reductions in the off-shore zone, with a significant degree of salinity of the soil profile. Meadow-chestnut solonetz are semi-hydromorphous soils and, in the region of the study, occupy more sublime areas, in particular the lower parts of the slopes of various forms of relief. The conditions for the formation of meadow-chestnut solonetz cause a greater leaching of their soil profile from easily soluble salts, carbonates and gypsum, which are accumulated mainly in the underneath-salolonetz horizons. Chestnut solonetz of the country between the rivers of Dnipro-Molochna belong to automorphic soils and have been formed within the elevations and in the upper parts of the slopes. The evolution of chestnut solonetz of the country between the rivers occurs mainly through their leaching of easily soluble salts, carbonates and gypsum, which in significant amounts have been accumulated mainly in the soil rock formation and in the horizons of the transition to it. Relatively large rounded closed downlands (pody) are the characteristics for the Black Sea lowlands. Solonetz is an important element of the soil cover of the lowlands (pody) of the country between the rivers of Dnipro-Molochna. The studied lowland’s (pody) solonetz should be divided into slightly salted and salty soils (solonchak) species. Salt species (solonchack) have been formed within the bases and lower parts of the slopes of the lowlands (pody) depression, under conditions of close occurrence of mineralized groundwater. They are distinguished by the high degree of salinity of the whole soil profile, the significant content of carbonates, the glueyness of the lower horizons, the absence or weak manifestation of signs of soliferous salinity of the eluvial horizon. Instead, soliferous species of solonetz are formed on the slopes of the lowlands (pody) with a deep degree of occurrence of groundwater and are characterized by a small amount of water-soluble salts, the number of which gradually increases with depth, a small content of carbonates in the soil profile, partially soluble with the upper-solonetz horizon. In addition to the lowlands (pody), the surface of the coastal zone of the country between the rivers is complicated by shallow and small oblate rounded closed declines, the formation of which is associated with processes of subsidence of rocks, the influence of sea, wind and temporary watercourses. Within such reductions, which were studied in detail on the territory of the Jagorlytskyi Peninsula, solonetz soils were formed mostly on the slopes, whereas the bottom soils were represented mainly by salt marshes (solonchack). The specific morphological feature of such solonetz is the surface eluvial horizon completely or partially eroded by sea waters, and a rather powerful upper-solonetz horizon of slightly sandy or sandy composition, formed by deposits of mainly lichen-marine origin. Based on the results of our own field studies, we have proved that the specific conditions of soil formation and migration of water soluble salts within the limits of lowlands (pody) and similar reductions of the dry steppe of the country between the rivers of Dnipro-Molochna lead to the formation of solonetz soils that differ significantly from those traditionally allocated in the generally accepted classifications of the soils of the region.

Soil cover patterns in the forest-steppe and steppe zones of the East European Plain

Abstract 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.

Содержание и распределение Mn, Fe, Ni, Cu, Zn и Pb в автоморфных почвах Полистовского заповедника

Содержание и распределение Mn, Fe, Ni, Cu, Zn и Pb в автоморфных почвах Полистовского заповедника

Content of Acid-Soluble Copper and Zinc in Background Soils of Komi Republic

Geochemical features of copper and zinc in soils of background landscapes of northeastern European Russia have been revealed. Soils of accumulative landscapes are enriched with copper and zinc compounds compared to those of eluvial landscapes. Humus horizons serve as a geochemical barrier for elements. Analysis of the sorption parameters of humic acids (HAs) shows that the actual content of the studied heavy metals (HMs) in soils is far from the maximum sorption capacity. The contribution of HAs to the total sorption of metals makes up 4% for copper and 21% for zinc. The distribution of HMs among the genetic horizons is more contrast in loamy automorphic soils than in sandy semihydromorphic and hydromorphic soils. Paired correlations have been revealed between the contents of copper and zinc in sandy and loamy soils, which points to the similarity of their biogeochemical migration in landscapes. An actual database has been created, which is foundational to schematic maps of the spatial distribution of elements in background soils. The geochemical assessment of the environmental status of soils has allowed establishing norms for the regional background contents of copper and zinc in taiga and tundra soils.

Trends of Soil Processes in Natural Landscapes of Mountain and Piedmont Provinces of Dagestan

Data of long-term researches for revealing the trend of modern processes of soil formation and degradation in the mountain and piedmont provinces of Dagestan are given. The aim of the researches was to study the modern soil-erosion and ecologic-ameliorative status of the soil cover and changes in the naturalresource potential of slope lands under the effect of natural and anthropogenic factors over a 50-year period. A strong effect of exogenic and endogenic factors on slope ecosystems results in development of erosion and degradation processes. The soil cover is formed under conditions of intensive geomorphologic, geochemical, and biological processes. The increasing anthropogenic load and climate aridization exert a strong effect on their dynamics. The comparison of data of earlier soil-erosion survey with modern ones shows great changes in the spatial pattern of eroded soils. The areas of noneroded lands became two times smaller over the period of studies. There is a tendency for a decrease in the areas of brown forest soils of a hydromorphic type of soil formation and for enlargement in the area of semihydromorphic and automorphic brown and chestnut soils. A great diversity of soil–plant cover in the areas with vertical zonality is related to differences in slope aspects, topography, and steepness. Soil evolution is characterized by a trend from hydromorphic and semihydromorphic to automorphic stages of soil formation.

Influence of Vegetation on the Lability Characteristics of Sandur Areas of the Bryansky Les Nature Reserve

We have assessed the influence of vegetation on the labile characteristics (acidity, total carbon and nitrogen content, and available nutrients) of automorphic soils of polydominant coniferous–broadleaf forests and dwarf-shrub–green-moss pine forests of the Bryansky Les Nature Reserve. Despite the comparable gross and grain size compositions of soil-forming rocks, the differences of soils of these forest types are determined by the influence of vegetation, mainly by its ability to form litters of different quality and to regulate the amount of precipitation percolating through the forest canopy and contributing to the nutrient removal. Soils of pine forests have a higher acidity and lower contents of total nitrogen, organic carbon, and available nutrients than do soils of coniferous–broadleaf forests. The stand of pine forests has a low crown density, which leads to more intensive nutrient removal by atmospheric precipitation infiltrating through the soil.

Characteristic of soils of Odesa City

In the article, the basic morphological features, physical and chemical properties of soils of Odesa, analyzed indicators nutrient content, humus pHN2O, soil particle size distribution. The composition of salts and absorbed bases in soils is established. The purpose of this study is to characterize the soil cover of Odesa City. 47 full-profile sections were laid in 9 key sections in the city area. Key areas are characterized by the different anthropogenic impact on the soil upper layer and intensity of its use. According to the result of the studies of soils in Odesa City, the following groups of soils are distinguished in the territory of the city: natural undisturbed soils, anthropogenically externally disturbed natural soils, anthropogenically deeply disturbed soils (urban-soils). For natural undisturbed and anthropogenically externally disturbed natural soils, heavy loamy and medium loam granulometric composition is characteristic in most cases. The upper horizons of the soils of the firth overspill have a lighter composition – from light loamy to sandy. The granulometric composition of urban soils is heavy loamy, during a tendency toward its alleviation due to the anthropogenic increase of the content of sand fractions and skeletal material. A characteristic feature of undisturbed soils of the Odesa City is fairly high variability in the nitrogen content of nitrification, mobile phosphorus and exchange potassium, and organic substance. The sum of the absorbed bases in natural undisturbed and anthropogenically externally disturbed natural soils, as in urban areas, is low. The ratio between calcium and magnesium ranges from 2:1 to 6:1. Automorphic soils are predominantly weakly solonetzic. Marsh soils are characterized by a certain increase in the proportion of sodium from the sum of the absorbed bases - up to 36.47 %. Natural humus soils are characterized by a lack of salinity. Meadow soils from the surface have a weak degree of chloride type of salinity, and an average and a strong degree of chloride type of salinity is noted down to the profile. Urban soils have a weak degree of chloride-sulfate salinization, associated with the use of mixtures against ice in winter. Marsh soils have a strong degree of soda-chloride type of salinity from the surface. Key words: Odesa, urban soils, anthropogenic transformation of urban soils.

Физико-механические свойства автоморфных таежных почв Республики Коми (по данным реологических исследований)

Физико-механические свойства автоморфных таежных почв Республики Коми (по данным реологических исследований)