Humus Horizon Research Articles

Морфолого-генетична та агрономічна характеристики контрастних за засоленням ґрунтів солонцевого комплексу Приорілля

The article presents the results of field and laboratory studies on the determination of the morphological, genetic and agronomic characteristics of the soils of the Solon complex of Prioril, contrasting in terms of salinity - the establishment of the peculiarities of the morphological structure of the profiles, the granulometric composition, and the parameters of the main agrochemical, salt and physicochemical parameters of the salt marsh of the meadow-black earth shallow salt marsh and black earth-meadow soil - as typical components of the salt complex of the Oril river valley. Standardized field survey and laboratory-analytical methods were used. It has been established that manifestations of halogenation increase with depth in the Luchno-chernozem salt marsh. Alkalinity in the humus-iluvial horizon increases to a strong degree, in deeper horizons - to a very strong one; the degree of salinity increases to medium, strong, and finally to very strong in the bedrock. According to the depth of the upper horizon of salt accumulation, this soil is classified as saline. The content of absorbed sodium in the humus-iluvial and illuvial horizons corresponds to the "saline" gradation. The chernozem-meadow soil is non-saline according to the content of toxic salts in the entire profile, there are no signs of physical and physico-chemical salinity. The content of the silt fraction in the salt marsh profile increases with depth and reaches its maximum value in the illuvial horizon, which is typical for salt marshes and is explained by the redistribution of soil colloids in the profile, the granulometric composition of the salt marsh in the humus-eluvial and illuvial horizons is light clay, in the humus-illuvial - medium clay. The profile of the chernozem-meadow soil is also heterogeneous in granulometric composition, which is heavier from medium loam in the humus horizon to heavy loam in the transitional horizons. The reason for this may be ancient alluvial processes that formed the soil-forming rock of the single-forest terrace. The content of humus in the salt pan in humus-eluvial and humus-iluvial horizons is average, the content of mineral (nitrate and ammonia) nitrogen is very low. The content of mobile potassium turned out to be elevated, and the content of mobile phosphorus was very high. In the chernozem-meadow soil, the content of humus in the humus arable horizon is high, in the first transitional one, it is average. The content of mineral nitrogen is low. The content of mobile phosphorus exceeds the upper limit of the high level by 3.5 times, and mobile potassium by 3.1 times, which is typical for the soils of closed depressions and is a consequence of long-term accumulation of surface runoff waters. Conclusions. The salt marsh complex of Priorillya with the number of salt marshes in the soil cover of about 50% is typical for the southern part of the Middle Forest Steppe in terms of the structure of soil profiles and soil halogenation. A characteristic feature of the studied salt marsh complex is the significant contrast of its components in terms of halogenation manifestations: at a short distance there are salt marsh highly saline salt marsh and leached chernozem-meadow soil without physical and physico-chemical signs of salinity.

Тяжёлые металлы и техногенные магнитные частицы в почвах рекреационной территории города Пермь (на примере экологической тропы Чапаевская)

The work focuses on the study of soils on the territory of the Chapaevskaya ecological trail in the city of Perm (Russia). The studied soils are subject to contamination by technogenic magnetic particles and heavy metals in their composition. The forest litter of the urbanity gray humus soil formed on the eluvial-deluvial deposits is contaminated with Cd, Cu, Ni, Co, and Zn. The urbanity gray humus horizon accumulates Cu and Zn. The values of the magnetic susceptibility of the highly magnetic phase of the surface horizon are high. The maximum value of the magnetic susceptibility of the forest litter was 55.64 × 10-3 SI. The bulk content of heavy metals and Fe in the highly magnetic phase is several times higher than in the soil before magnetic separation. Keywords: POLLUTION, MAGNETIC SUSCEPTIBILITY, ENVIRONMENTAL ASSESSMENT, URBANITY GRAY HUMUS SOIL, CIS-URALS

Agroecological assessment of agricultural soils fertility in the Iglinsky region, the Russian Federation

The article provides an assessment of soil fertility indicators of agricultural lands in the northern foreststeppe of the Republic of Bashkortostan within the Iglinsky region (Russian Federation). The content of humus, mobile phosphorus, exchangeable potassium, the thickness of the humus horizon, granulometric composition, morphological properties and soil washout were studied. It was revealed that the soil-forming process occurs on rocks of different ages and genesis, such as diluvial carbonate and carbonate-free clays and heavy loams, limestone eluvium, sandstone eluvium and alluvial deposits, which determine the diversity of the soil cover. In the study area, water erosion processes are developing, influenced by anthropogenic and natural factors such as planar and linear washout on slopes with a steepness of more than 2–3° and high ploughing of agricultural land. In terms of humus content, low-humus and medium-humus soils are widespread, accounting for 45.5 and 40%, respectively. The soil map was corrected and digitised to identify the main types and subtypes of soils, indicating the varieties at a scale of 1: 25,000. Digitised maps, taking into account the current state of soil fertility, are used to develop projects for inter-farm and intra-farm land management of organisations of the agro-industrial complex, state cadastral valuation of agricultural land, determination of land tax and development of measures to improve soil fertility.

LANDUSE FEATURES IN A MOUNTAIN AREA AND THEIR EFFECTS ON THE PROCESS OF SYLVATISATION (STRYY DISTRICT LVIV REGION)

The Skole District that is nowadays a part of newly established Stryy District (Lviv Region) is entirely situated within the range of the Ukrainian Carpathians. Its area encompasses the Skolivsli Beskydy and the Stryy-San Highland physiographic regions featuring a dominance of considerably high altitudes above sea level, terrain disarticulation, and afforestation. Establishing new villages alongside rural population’s natural increase and land reforms (the capitalist stage of land use (after the abolition of serfdom in 1848) and Soviet stage of land use) called for respective increase in agricultural lands. Forested lands in the Ukrainian Carpathians were the source for such an increase therefore cropland and pasture lands were emerging from deforestation. Harsh weather conditions and low soil fertility significantly impacted the further agricultural land uses in the mountainous region. However, wide-scale decline of agricultural lands occurred in the period of the collapse of the former USSR due to decline of collective and state farms. As a result of denationalization with subsequent privatization of agricultural lands there are nowadays 31 303 land owners and land users in the study area, 97,54 % of which are physical persons. At the same time, despite such remarkable figures citizens share less than a half of total lands for agriculture, residential and construction purposes, whilst the state forestry enterprises are using 51,11 % (75 173,50 ha) in total. In contrast to lowlands, animal farming and husbandry in the Skole District is held exclusively by households. In recent years local animal husbandry is experiencing the livestock decline that leads to certain reduction in the share of both hay meadows and pasturelands. Thus, from 2009 to 2016 the total area of fodder lands in the district decreased by 65 ha (ca. 0,2 % of total privately owned agricultural lands). I assume that ongoing land reform will cause further increase in fallows in the Skole District. In order to better comprehend the processes of spontaneous reforestation (sylvatisation) in a mountain region (the Pohartsi boundary, Koziova village, Stryi district, Lviv regionthe ) four study plots were selected representing the successional sequence: forest → pasture → hay meadow → arable lands. The study showed that areas that were previously used for pasture and were not plowed, are restored to their natural state much faster. These areas are characterized by satisfactory physical, physico-chemical and biotic properties. The decrease in acidity towards the neutral side is explained by an increase in the activity of catalase and urease by approximately 1.5 times. In connection with the developed grass cover, slightly higher nitrogen values were recorded in the upper soil horizon. Due to the absence of a regular annual supply to the base and replenishment of its nutrient reserves due to precipitation and waste of dead phytomass, the content of humus in the upper horizon of the base is half as much as under forest biogeocenoses. Plowing (overturning the lower horizons to the mountain, and vice versa) is a very strong anthropogenic factor, which leads to the almost complete destruction of natural vegetation on the cultivated area and a radical change in the main properties of the soil cover. According to some indicators: physical (total sparability), physico-chemical (nitrogen nitrate and ammonia), biotic (urease, catalase, biomass of microorganisms) in the upper humus horizons were even somewhat close to anthropogenically unaltered ecosystems. However, the changes in the indicators of the density of the soil structure and its solid phase corresponded to the depth of plowing. And the humus content was several times lower than under forest biogeocenoses. Areas that were not plowed in the past are restored due to the main rock of the region Picea abies (L.) Karst.. Areas that were devastated in the past are recovering much more slowly. Such areas begin to overgrow with Alnus incana (L.) Moench., Rosa canina L., Bеtula and others Key words: land use; land owners and land users; fallows; agricultural lands; mountainous region; Skolivski Beskydy.

Sorption capacity of organic matter to heavy metals and its use for polluted soils recover soils recover

The article considers the results of leached chernozems and yellow soil research in Central Russia and in the South of Central China. The research has demonstrated that organic matter has an increased sorption capacity for heavy metals (HM), including lead (Pb) and cadmium (Cd), which are hazardous environmental pollutants. Studies conducted on chernozems demonstrate features of HM migration along a soil profile. Thus, the total content of elements accumulates in the upper humus horizon, further down the profile it gradually decreases, following a decrease in an amount of organic matter. In a soil-forming rock an accumulation of metals is again noted due to the alkaline reaction of soil solution and silt fraction, which is enriched in soil-forming rocks. A significant increase in elements content in soils of arable land (farmland soils) was revealed in comparison with a fallow territory and a forest belt. This phenomenon explains by an additional supply of HMs as an admixture of mineral fertilizers applied on plowed chernozems. In addition, HMs are also appear as a result of agricultural machinery operations during flammable fuel combustion. The ability of organic matter to increased sorption of HMs can be used to restore heavily polluted areas. Farmland soils of Sichuan province were studied as a model experiment. Keywords: CHERNOZEMS, YELLOW SOIL, HEAVY METALS, LEAD, CADMIUM, TOTAL CONTENT, EXCHANGE COMPOUNDS, VORONEZH OBLAST, SICHUAN PROVINCE

Сорбционная способность органического вещества к тяжелым металлам и ее применение при восстановлении загрязненных почв

The article considers the results of leached chernozems and yellow soil research in Central Russia and in the South of Central China. The research has demonstrated that organic matter has an increased sorption capacity for heavy metals (HM), including lead (Pb) and cadmium (Cd), which are hazardous environmental pollutants. Studies conducted on chernozems demonstrate features of HM migration along a soil profile. Thus, the total content of elements accumulates in the upper humus horizon, further down the profile it gradually decreases, following a decrease in an amount of organic matter. In a soil-forming rock an accumulation of metals is again noted due to the alkaline reaction of soil solution and silt fraction, which is enriched in soil-forming rocks. A significant increase in elements content in soils of arable land (farmland soils) was revealed in comparison with a fallow territory and a forest belt. This phenomenon explains by an additional supply of HMs as an admixture of mineral fertilizers applied on plowed chernozems. In addition, HMs are also appear as a result of agricultural machinery operations during flammable fuel combustion. The ability of organic matter to increased sorption of HMs can be used to restore heavily polluted areas. Farmland soils of Sichuan province were studied as a model experiment. Keywords: CHERNOZEMS, YELLOW SOIL, HEAVY METALS, LEAD, CADMIUM, TOTAL CONTENT, EXCHANGE COMPOUNDS, VORONEZH OBLAST, SICHUAN PROVINCE

Environmental aspects of the use of land resources

The article considers ecological aspects of using land resources. The main ecological aspects of using land resources are identified according to three main groups: soil conditions, relief characteristics, climatic conditions. Furthermore, the soil conditions of land holdings and land use are characterized by such indicators as: types of soils, the thickness of the humus horizon, its water permeability, erodibility, the content of humus, minerals, dusty and fine sand fractions, compaction of the soil layer, etc. Among the characteristics of the relief, the most significant ones for ensuring the ecological sustainability of land ownership and land use include: steepness, shape, length and exposure of the slope, height difference and the degree of dismemberment of territories by ravines, streams and hydrographic networks, the magnitude of local bases of erosion, etc. Among the climatic conditions, solar radiation (light), temperature and water regimes, as well as other conditions forming the microclimate are important. It has been established that ensuring the sustainable use of land resources, taking into account ecological aspects, is a complete set of methods and tools, with the help of which the processes of land use and protection are organized, regulated and coordinated, and the reproduction of soil fertility as a natural resource element of public wealth and a specific ecological feature is ensured. Currently, the use of land resources must be carried out on an ecological basis, that is, while ensuring ecological balance in the adjacent territories in the process of interaction between man and nature, coordination of ecological and economic interests. It is emphasized that the main principles of ensuring the ecological sustainability of using land resources are: the obligation of greening of nature use in general and the land use system in particular; in the process of formation of land uses and land ownership, it is necessary to ensure the fulfillment of basic ecological, socio-economic and technological conditions; the criteria of the rationality of formed land uses are high economic, ecological and recreational efficiency and, as a result, preservation of the health of people living in the given territory; the formation of ecologically sustainable land use must be supported by a system of ecological, including environmental protection, substantiation and regulation. Key words: land, agricultural lands, land resources, use of land resources, ecological aspects.

Impact of the B-Plus white pearl (Belyi Zhemchug) preparation on the spring frost tolerance, yield and quality of apple crops

In 2021–2022, experiments were conducted at the Laboratory of Fruit Crop Resistance Physiology, All-Russia Institute for Fruit Crops Breeding (VNIISPK), to investigate the action of the “White Pearl Antifreeze” (Belyi Zhemchug Antifriz) phytomodulator and the “White Pearl Drip Ca + Mg” (Belyi Zhemchug Drip Ca+Mg) phytocorrector produced by the AgroPlus Group of Companies, LLC. Experimental and control plots were characterized by dark-gray forest soils with a humus content of 3-4 % and a humus horizon thickness of 30–35 cm. Apple trees cv. Sinap Orlovsky (VNIISPK) grafted on semi-dwarf rootstock 54-118 were planted in 2013 according to a 6 x 3 m scheme. Natural grassing was used in row spacings; herbicides were applied around the seedlings. The experimental design included: 1) control (water treatment) and 2) foliar treatment with a 1 % solution of “White Pearl Antifreeze” + a 1 % solution of “White Pearl Drip Ca+Mg”. The experiment was conducted in three replications with five observed trees in each. Our aim was to assess the effect of the mentioned preparations on the spring frost tolerance, yield, and quality of apple fruit under the weather conditions of 2021. Foliar treatments with the studied preparations reduced the frost damage to Sinap Orlovsky apple buds by 6.3 % at -3.5 °С and by 10.4 % at -4 °С. The conducted summer foliar treatments with the organomineral mixture under study intensified the growth and ripening of apple fruit. The improved protein-carbohydrate metabolism, water regime, photosynthetic activity, and donor-acceptor leaf–fruit relations increased the fruit weight by 10 g and the yield by 1.8 times. The conclusion is made that the B-PLUS “White Pearl Antifreeze” preparation exhibits a complex effect in terms of increasing plant tolerance to low-temperature spring damage, thus improving the yield and quality of apple crops.

Soil fertility analysis in the Republic of Bashkortostan

The manuscript presents the materials of soil fertility analysis of agricultural lands in the north-eastern forest-steppe of the Republic of Bashkortostan in the conditions of the Salavatskiy district of the republic (Russian Federation). Agrochemical analysis of the humus accumulation, mobile phosphorus, exchangeable potassium was carried out, morphological properties were studied, the thickness of the humus horizon, granulometric composition and soil erosion were determined. During the 49-year period of agricultural land use, it was revealed some of the medium-humus soils passed into the category of high-humus, caused by the fact that the arable lands were not used for cultivating crops and they were withdrawn from circulation and sown with many-year-old grasses. As to the thickness of the humus horizon, low-yielding soils predominate, which occupy 60.11%, average 32.9%. The main land area belongs to slightly washed soils of 67,445.2 ha (58.2%) and unwashed 36,985.5 ha (31.9%). Agricultural lands are mainly characterized as medium-humus (80.3%) and obese (12.1%) ones. Based on the results of the research, an adjustment, digitization and a new soil map of the Salavatskiy district was made with the allocation of the main types and subtypes of soils with the indication of varieties on a scale of 1:25,000.

Interplay between Selected Chemical and Biochemical Soil Properties in the Humus Horizons of Grassland Soils with Low Water Table Depth

Grasslands are the most carbon-rich of all agricultural ecosystems, but are also the most endangered. The global area of grassland decreased during the 20th century, mainly due to conversion to arable land, improper management, and abandonment. Due to ongoing climate change, maintenance of an adequate level of soil organic matter is of primary importance, not only to maintain the productive function of the soils, but also to ensure their role as carbon stores. The main aim of this study was to assess the linkages between selected chemical and biochemical soil properties in alluvial grassland soils, characterized by a low water table. The area under study was located in the Koło Basin, central Poland. Soil parameters, such as total organic carbon, total nitrogen, pH, phosphorus, magnesium, and potassium contents, as well as enzymatic activity and soil microbial structure were studied. Positive correlations were observed between total organic carbon content and the following enzymatic activities: dehydrogenase (r = 0.63), acid phosphatase (r = 0.69), and alkaline phosphatase (r = 0.86). There was a significant correlation between fungi abundance and phosphorus and potassium contents, and between actinobacteria abundance and total organic carbon content.

An Anthropogenic Effect on Alluvial-Meadow-Forest Soils in the Floodplain of Kura River (Azerbaijan)

The issues of genetic features, classification position and diagnostic indicators of floodplain-alluvial soils are considered. Alluvial-meadow-forest soils are fairly widespread under the high quality tugai forests of the floodplain of the Kura River. The territory has favorable relief conditions, a dry subtropical climate, as well as resources of the water regime. The humus content in the upper horizons is 4.2-4.5% and decreases with depth to 0.8%. In the buried humus horizons, an increase up to 2.2% is observed. The amount of total nitrogen in the horizons is 0.21-0.26%. The results of the analysis indicate differences in the gross chemical composition of forest and cultivated alluvial-meadow-forest soils. Irrigated soils were identified as an independent type.

Erosion control properties of self-seeded forests that appeared in forestless areas of ravine-gully systems

Abstract During land unsoldering in Ukraine, so-called “self-seeded forests” appeared on lands that had not been used for agriculture for a long time. The purpose of the research is to find out the erosion control properties of self-seeded forests. Twelve locations of natural regeneration of various types of woody plants on the ravine-gully system of Cherkasy region were chosen as research sites. Self-seeded woods have a structure of different ages from 8 to 25 years. Most of them are represented by mixed stands, which increase their biological stability. They are better adapted to the current climate change. The formation of uneven-aged stands of natural regeneration with high resistance and erosion control properties was noted. According to the qualitative indicator of productivity, the natural regeneration turned out to be different, which was primarily caused by forest sites conditions, in particular, the steepness, the position on the slope, and the thickness of the humus horizon of the soil. The hardness of the soil was determined in the range from 17.1 to 19.0 kg/cm2, which corresponds to an average loose state. The hardness of the soil in the control was 23.9 kg/cm2, which corresponds to its compacted state. The water permeability of the soil under the studied stands was 11.1–27.3 (control – 8.9) mm/min, which characterizes it from the best to chasm. The obtained soil water permeability data confirm the rapid transfer of surface runoff to subsoil, which prevents the development of erosion processes. Natural regeneration on the slopes of the ravine-gully system is determined to be successful, although it requires considerable time for the formation of full-fledged plantations.

Stable Carbon Isotopic Composition (δ13C) as a Proxy of Organic Matter Dynamics in Soils on the Western Shore of Lake Baikal

Abstract Assessing the main factors that control carbon dynamics in soils is an urgent problem in the context of modern climate change. The analysis of stable carbon isotope (δ13С) composition is one of the approaches to understanding this dynamics. The study was carried out in the landscapes of the southeastern slope and foothills of the Primorskii Range, characterized by contrasting physico-geographical conditions. Climatic parameters, spatial variations in the composition of stable carbon isotopes and their distribution in soil profiles, and soil physicochemical properties controlling carbon dynamics have been analyzed. The soil humus horizons formed in mountainous tundra and steppe landscapes manifest the highest δ13С values (–24.72 and –23.97…–24.75‰); whereas the lowest (–25.61…–27.18‰) values are registered in the mountainous taiga soils. Based on the calculation of linear dependence between δ13С values and the total carbon content in soil, which varies with the depth, the carbon turnover intensity was determined using the slope of linear regression. It was revealed that under the contrasting conditions of mountainous tundra and steppe landscapes, the climate (deficiency of heat and moisture) has a significant impact on the intensity of organic matter transformation, blocking the effect of edaphic (soil profile) factors. Under more favorable climatic conditions of mountainous taiga landscapes, the dynamics of organic matter in soils is controlled mainly by edaphic factors.

RIVER-BASIN SYSTEMS OF SMALL RIVERS OF THE WESTERN PODILLYA IN THE CONDITIONS OF ANTHROPOGENIC LOADS: A COMPARATIVE ANALYSIS

The results of complex studies of the basins of the small rivers Dzhuryn, Gnizna, Nichlava, from the point of view of the transformation of natural complexes, the introduction of optimal forms of nature use and effective systems of nature protection for the effective management of the process of ecological, social and economic development are highlighted. Land use optimization models of basin systems have been developed, and an integrated network of nature conservation areas and protected and recreational facilities has been substantiated. The conducted comparative analysis of hydro-ecological, nature protection and land use parameters made it possible to establish.
 The problems of nature management and nature protection in the river basin are closely related. Analysis of the structure of nature use, the ratio of ecologically safe and ecologically dangerous forms within the upper, middle and lower reaches of river valleys demonstrates the degree of balanced nature use and the effectiveness of nature protection regimes.
 The development of the materials of the monograph took place in the process of field research by the authors as part of data collection for writing candidate and master theses. In addition, the authors rely on their own publications in scientific periodicals and approbation of materials in reports at scientific forums on the problems of nature management and nature protection in the basins of the small rivers Dzhuryn, Nichlava, and Gnizna.
 Special attention is paid to small rivers, because they perform extremely important functions in the formation of the hydrological regime of surface waters, directly influencing the system of relations with the local population, being in natural resource relations with them. Small rivers are the only water arteries in settlements, performing economic, recreation and health, aesthetic, climate-regulatory functions. Their general condition is derived from the peculiarities of interaction of local communities with the natural environment, which is based on the principles of productive life of people in harmony with nature. Achieving harmonious relationships primarily depends on the level of ecological culture of citizens, their tolerant and responsible attitude towards nature.
 The small rivers of Western Podillia: Dzhuryn, Gnizna, Nichlava were considered in a comparative analysis with the aim of highlighting general and individual deviations of basic parameters from their normative values, substantiating measures for their optimization. The object of the research is the basins of small rivers of Western Podillia: Dzhuryn, Gnizna, Nichlava. The subject is a comparative analysis of hydrogeoecological and nature protection parameters of anthropogenic influence on their basins.
 The general similarity of the natural and climatic conditions of the territory, the proximity of the location does not guarantee the similarity of anthropogenic loads on river basins.
 The conducted comparative analysis of hydroecological and nature protection parameters of river basins demonstrated. low forest coverage of the territories, which will contribute to increased soil erosion, a specific water and wind regime, less intensive assimilation of greenhouse gases, etc. The indicators of the protection of river basins differ significantly, but all of them are significantly inferior to the optimal value within 10.5%. The indicators of plowing of river basins differ significantly. They are significantly higher than the normative ones by approximately 2 times. The negative consequences of excessive plowing are manifested in increased erosion processes, activation of surface runoff into the river washed humus horizon with mineral, organic fertilizers, toxic chemicals, which definitely manifests itself in the deterioration of water quality. The high built-up area of the Nichlava river basin has a negative impact on the growth of pollution by domestic sewage, solid household waste, the absence of water protection zones within the boundaries of settlements, etc. In general, we have reason to claim that the river landscapes are highly economically developed due to the dominance of anthropogenic lands, on almost 2/3 of the area. Accordingly, the indices of anthropogenic transformation of natural lands by economic activity are high.
 Key words: small river, Western Podillia, Gnizna, Dzhuryn, Nichlava.

Features of modern genesis of the Ishim steppe watershed plain soils

The genesis main directions of the Ishim steppe watershed plain soils depending on their economic use (arable land, forest belt, abandoned land) during the 1950s – 2020s were revealed. Within the studied region, soils were diagnosed on lands of different use. It is shown that the regional morphogenetic feature of all watershed plain soils is the tonguing of the humus horizon, which is reflected in their classification status by the allocation of a dark-tonguic subtype of the soils. Differentiation of the agrodarkhumus horizon into two subhorizons under the influence of plane-cutting processing was revealed in the agrozem, prevailing by area. The manifestation of postagrogenic transformation of soils occurring under forest belts and under deposits with herbaceous vegetation is determined. Postagrogenic soils are characterized by a granular structure, higher reserves of humus and total nitrogen in a layer of 0–20 cm compared to agrozems. In the soil of the forest belt, a coarse-humus neo-horizon was formed, which is not typical of steppe soils. The soil under abandoned for a long time grassland has signs of dark humus horizon progradation to a state close to a virgin one. The additional surface moistening of micro-subsidence soils causes them to have a higher humus content and its reserves in the 0–100 cm layer, deeper leaching of carbonates, the formation of a clay-illuvial horizon in the carbonate-free zone and prevents the formation of a gypsum horizon. The groundwater level raising in the modern period, which is a consequence of the mass plowing and functioning of impenetrable protective forest belts in the study area, caused the appearance of neo-hydromorphism in watershed plain soils and the formation of quasi-clay subtypes. The results indicate the regional specificity of the genetic properties of the Ishim steppe watershed plain soils that distinguish them from their European counterparts, as well as the influence of agrogenic transformation as an anthropogenic factor on them. This influence is reflected in the morphology of soils, their humus state, the nature of the carbonate and gypsum profiles, the processes of halogenesis in them and the variety of salt profiles.

Radionuclide activity in cryoconite from glaciers of the Central Caucasus, Russia

This work presents the results of a study of radionuclide activity in cryoconite from glacier and glacial soil of the Central Caucasus. Cryoconite were sampled from the surface of the Garabashi glacier, and soil samples were taken from the humus horizon of periglacial mountain forest-meadow soil. Measurements were performed with low-background germanium gamma spectrometers located inside a passive shield consisting of ∼20 cm of copper, ∼15 cm of lead, and ∼8 cm of borated polyethylene. The specific activity of radionuclides (Be-7, K-40, Th-232, U-235, U-238, Cs-137) was established. It was revealed that all measured spectra contain γ-lines from decays of K-40, decay chains of U-238, U-235 and Th-232. In addition, the spectra of cryoconite samples from the Garabashi glacier show a 477.6 keV line from the decay of the cosmogenic isotope Be-7, and in the soil sample a 661.7 keV line from the radionuclide Cs-137. No radionuclide Be-7 was detected in the mountain forest-meadow soil. Radionuclide Cs-137 is present in the soil sample, while in cryoconite, is not detected. Radioisotope activities in the Garabashi glacier cryoconite, except for the cosmogenic isotope Be-7, do not differ significantly in terms of mass, i.e., the content of K-40, U-238, U-235 and Th-232 in them is approximately the same. The activity of all the studied radionuclides in the soil sample compared to cryoconite samples is lower, although the differences are not significant, except for Th-232, whose activity in soil is almost two times lower.

FEATURES OF VERTICAL MIGRATION OF HEAVY METALS IN SOILS OF VARIOUS TYPES OF FOREST BIOGEOCENOSIS DURING AEROTECHNOGENIC CONTAMINATION WITH LEAD-CONTAINING DUST

We obtained data on radial migration of pollutant elements in soils of spruce, birch and black alder forests that had been subjected to air-dust contamination with lead-containing wastes. This waste was stored in a waste dump during 2015–2018 and then the waste was moved to a special landfill. We sampled each layer of soil and forest litter at intervals of 2 cm. The study area has strongly and moderately acidic, non-saturated, medium and low-humus, well-drained forest soils. We used the element concentration (or anomaly) coefficient and the radial contrast coefficient to assess the TM migration activity.
 The highest levels of contamination are characteristic of forest litter. The intensity of element accumulation in litter is determined by two factors: the size of the litter itself and the distance of the sample site from the emission source. Well
 developed spruce litter is a biogeochemical barrier, which significantly reduces the risk of pollution of the humus horizon of soils with cadmium and lead, as well as the flow of metals into deeper soil layers and groundwater. At the same time,
 the migration mobility of iron, nickel and, to some extent, copper remains. The poorly size litter of birch and black-alder
 forests has less pronounced protective properties.

δ15N in Birch and Pine Leaves in the Vicinity of a Large Copper Smelter Indicating a Change in the Conditions of Their Soil Nutrition

δ13C and δ15N were analyzed in the leaves of Pinus sylvestris L. and Betula spp. under the conditions of severe heavy metal (Zn, Cu, Cd, and Pb) contamination. Twenty-seven plots located near the Karabash copper smelter (Russia) were studied. No reliable correlation of 13C in tree leaves with the level of pollution was observed. δ15N, both in Pinus sylvestris and Betula spp., increased similarly in polluted areas. δ15N was increased by 2.3‰ in the needles of Pinus sylvestris and by 1.6‰ in the leaves of Betula spp. in polluted plots compared to the background ones. The probable reasons for the increase in δ15N were estimated using multiple regression. The regression model, which includes two predictors: δ15N in the humus horizon and the occurrence of roots in the litter, explains 33% of the total variability of δ15N in leaves. Thus, in ecosystems polluted with heavy metals, the state of trees is determined not only by the direct toxic effects of heavy metals but also by indirect ones associated with the features of plant mineral nutrition. This fact opens the way to the search for opportunities to control the state of plants in disturbed ecosystems by regulating the content of mineral nutrition elements.

Paleoecology During the Creation of a Large Boldyrevo Kurgan of the Yamnaya Culture in the Southern Cis-Urals, Russia

This study focuses on a short-term pedochronosequence of Kurgan № 1 at the Boldyrevo IV kurgan cemetery in the Orenburg Region of the Southern Cis-Urals. According to archaeological findings, the kurgan was built over several decades by people of the Yamnaya (Pit-Grave) culture of the Early Bronze Age (around 5500 BP), with the exact time of its building to be confirmed by radiocarbon dating and further archaeological information. A comparative analysis of the four earthen constructions of the kurgan and the paleosols buried under those constructions was conducted. Results suggest that the kurgan building period was accompanied by the following changes in paleosol morphology and physicochemical properties: the humus horizon acquired a tonguing-like lower boundary, decreased organic carbon content and magnetic susceptibility, while the whole profile was characterized by increasing degree of zooturbation; the impregnation by carbonates in the middle part of the profile and the contents of carbonate carbon, gypsum, and exchangeable sodium increased. Similar trends of morphological and physicochemical changes were observed in the materials of the kurgan constructions. Based on these findings it can conclude that the climate went through aridization rise during the period of the kurgan building. The paleobotanical data from palynological and microbiomorphic analyses indicate that there was a tendency for paleoclimate aridization and, possibly a cooling trend during the studied period of the Yamnaya culture, which was probably more arid than the modern climate.

Soil and Vegetation Development on Coal-Waste Dump in Southern Poland.

As an anthropogenic element of urban landscapes, coal heaps undergo changes due to both natural and anthropogenic factors. The aim of this study was to determine the common development of soil under the influence of vegetation succession against a background of environmental conditions. Vegetation changes and soil properties were analysed along a transect passing through a heap representing a particular succession stage. It was found that changes in the development of vegetation were closely related to the stages of coal-waste disposal, where the initial, transitional, and terminal stages were distinguished. The mean range of pH (H2O) values in the profiles was 6.75 ± 0.21 (profile 1), 7.2 ± 0.31 (profile 2), 6.3 ± 1.22 (profile 3), and 5.38 ± 0.42 (profile 4). The organic carbon (OC) content in all samples was high, ranging from 9.6% to 41.6%. The highest content of total nitrogen (Nt) was found (1.132%) in the algal crust and sub-horizon of the organic horizon (Olfh-0.751%) and humus (A-0.884) horizon in profile 3 under the initial forest. Notable contents of available elements were found in the algal shell for P (1588 mg∙kg−1) and Mg (670 mg∙kg−1). Soil organic matter content was mainly dominated by n-alkanes (n-C11-n-C34) and alkanoic acids (C5–C20). Phytene and Phytadiene were typical for the algal crust on the initial pedigree. The initiation of succession was determined by the variation in grain size of the waste dumped on the heap and the variation in relief and associated habitat mosaic. Algal crusts forming on clay–dust mineral and organic material accumulating in the depressions of the site and at the foot of the heap can be regarded as the focus of pedogenesis.