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In this study, we examined the influence of long-term conventional tillage on the water-physical, chemical properties, and composition of the organic matter of chernozems. The study has been conducted on an arable plot subjected to water and wind erosion in the Pre-Ural steppe zone (Republic of Bashkortostan, Russia). Soil samples were collected from non-eroded and eroded arable plots as well as from an adjacent pristine forest windbreak. Key structural fragments of soil organic matter under different land use types were identified and quantified using 13C-NMR spectroscopy. The results showed that the water-physical properties deteriorated in agrochernozems: the number of valuable soil aggregates decreased and the soil bulk density increased, which may limit the growth of crops. The soil organic matter content for the different samples varied in the following direction: arable non-eroded > forest windbreak > arable eroded. It has been found that long-term plowing by conventional methods decreases aliphatic and increases aromatic structures in soils. As a result of the reduced inputs of plant residues, the processes of humification slowed down compared to unplowed soils. To increase soil fertility and carbon sequestration potential, it is necessary to stop degradation processes and implement conservation tillage practices. [ABSTRACT FROM AUTHOR]

The morphological, water-physical and chemical properties, basal respiration of the southern chernozem (Chernozem Haplic Endosalic) and erosional sediment in the Trans-Ural steppe zone (Republic of Bashkortostan, Russia) were studied. The surface soil horizon significantly differs from the sediment by the better structure and water aggregate stability. The particle size distribution of the sediments, due to erosion, contains more silt and clay fractions compared to the slope soil. It indicates a great potential for the carbon saturation of the soil which is limited by degradation. The slope soil is slightly saline, the type of the salinisation is sulfate with the participation of hydrocarbonates. The СО2 emissions, the organic carbon and alkaline-hydrolysable nitrogen content is low; and significantly lower than in the erosional sediment, but the content of exchangeable cations and water-soluble salts is higher. The structural composition of the humic acid (HA) extracted from the soil and erosional sediments was determined by 13C NMR spectroscopy. Aliphatic structural fragments predominate (65%) with a maximum signal level in the area of C, H-alkyls in the HA of the surface horizon. In the HA of the erosional sediment, the proportion of aromatic structural fragments is higher (up to 59%), which is associated with the processes of hydrolysis and condensation. In the HA of the slope soil, the formation of predominantly C, H-alkyls, oxygen-containing groups, including carboxyl ones, takes place. Differences in the composition of the structural fragments and functional groups of the soil and sediment HA are due to the different stability of the organic matter under conditions of the development of the soil erosion processes. [ABSTRACT FROM AUTHOR]

This paper presents the results of studying the soils at the archeological site of the Tyater-Araslanovo-II settlement located in the Republic of Bashkortostan, eastern European Russia. The settlement functioned in the 15th-12th centuries BCE (the Late Bronze Age). We compared the soil properties at four sites in the study area: archeological (1), buried (2), affected by long pyrogenic exposure (3), and background site (4). In soil samples, the total carbon content, the fractional composition of humus and organic matter characteristics, alkaline hydrolyzable nitrogen, total phosphorus, mobile phosphorus, potassium, absorbed calcium and magnesium, pH, particle size distribution, basal soil respiration, and optical density were estimated. The study results showed the anthropogenic impact on the archeological site's soils. The newly formed AU horizon at the archeological site (1), affected by the cattle summer camp, was richer in soil nutrients and agrochemical properties, namely, the content of exchangeable and gross forms of phosphorus, alkaline hydrolyzable nitrogen, and exchange cations of the soil absorbing complex compared to the reference soil (4). For the pyrogenic layer (AU[hh]pyr) from the ancient furnace (fireplace) (3), the mobile and total forms of phosphorus were several times higher than those in the reference soil (4) but inferior regarding other agrochemical parameters. Thus, the activities of ancient people (especially cattle breeding) greatly influenced the properties of the soil. [ABSTRACT FROM AUTHOR]

The article presents the results of complex research (research was conducted in 2019) of the Botanical natural monument territory "Pine forest near Venetsiya village" (Russia). In 2007, part of the nature monument territory was destroyed by a hurricane, resulting in massive windfall. The purpose of the research was to study the processes of evolution of natural complexes (vegetation and soil cover) in the areas affected by the hurricane. Classification of vegetation was done according to the Braun-Blanquet and Kopečký and Hejný approaches. NDVI (Normalized Difference Vegetation Index) was used to estimate the amount of photosynthetically active biomass. Changes in morphological, physical and chemical properties were studied in the soil cover. The conducted research showed that the vegetation of the natural monument is represented by relict pine and broad-leaved pine forests. Under the pine canopy linden and birch are dominated. In the herb layer grow in various combinations of nemoral and boreal species. Soil cover is represented by Gray-humus (Umbric Luvisol). There is a strong transformation of vegetation in the areas damaged by the hurricane in 12 years (2007-2019). There is an active formation of highly productive herbaceous vegetation and renewal of deciduous stands, which leads to an increase in biomass (confirmed by changes in NDVI). The terminal stage of the restoration succession will be the formation of secondary deciduous and mixed nemoral forests. The active development of grass vegetation leads to the formation of a sod horizon on the surface of the soil with a thickness of about 14 cm. There is also an increase in the content of organic carbon, alkaline-hydrolyzable nitrogen and mobile phosphorus, the value of electrical resistivity increases and acidification of the soil solution. [ABSTRACT FROM AUTHOR]