Organic carbon and particle size distribution of aggregates from chernozem under arable land and shelterbelt

The particle size distribution (PSD) and the content of organic carbon (Corg) in dry and water-stable aggregates were determined in the upper layer of chernozem under arable land and shelterbelt. In water-stable aggregates, the Corg content is 1.2-1.5 times higher than in dry sieving aggregates. Dry sieving and water-stable aggregates of arable chernozem consist of particles identical in terms of the PSD. And in the chernozem under the shelterbelt the content of physical clay increases with a decrease in the size of the aggregate in water-stable aggregates isolated from the fraction of dry sieving < 1 mm.

Particle-Size Distribution in Soils of the Khankaiskiy Nature Reserve (Primorye Territory)

Soil texture is determined and the features of particle-size vertical distribution in soils of different landscapes of the Khankaiskiy Nature Reserve are considered. Three variants of the distribution of clay (&lt;0.001 mm) and physical clay (&lt;0.01 mm) fractions along the vertical profiles soils are identified: accumulative, regressive, with a maximum in the middle-profile horizon and with their approximately equal contents in the upper and the lower horizons. A regressive variant is revealed in burozems gleyic, podzoliс-brownzems, dark-humus gley and alluvial meadow gley soils. These soils are characterized by a medium loamy sandy-coarse-dusty composition of the upper horizons and a light- or medium-loamy composition of the middle and lower parts of the profile. The distribution of fine fractions along the profile is observed with a gradual decrease in their content with depth in typical burozems and alluvial meadow gley-ic soils, while the texture of the layer changes from medium loamy to light loamy. The vertical distribution of fine fractions with a maximum in the middle part of the profile is revealed in mucky gley soils. The profile is formed under the influence of a combination of the floodplain process with the introduction and redeposition of suspended particles and gleying. The lithological specificity of the accumulation of the initial parent materials plays a decisive role in the differentiation of fine fractions in the soil profile.

FEATURES OF TEXURE OF SOILS OF THE KHANKAISKIY NATURE RESERVE

Изучение гранулометрического состава почв Ханкайского заповедника показало, что профили почв представляют собой многослойные спектры различного литологического сложения. Сложность почвенных профилей по гранулометрическому составу определяется степенью проявления поемного и аллювиального процессов, литологическими особенностями почвообразующего материала. По типу сложения выделено несколько литологических групп. Темно-гумусовые глеевые, аллювиальные луговые глеевые почвы и буроземы глееватые отличаются резкой дифференциацией профиля по гранулометрическому составу на верхнюю легкую и нижнюю глинистую толщу. Для этих почв отмечено наибольшее содержание фракций физической глины и ила по всему почвенному профилю. Буроземы типичные и аллювиальные луговые глееватые, вышедшие из зоны затопления, характеризуются литологически однородным легким составом. В этих почвах выявлено высокое содержание фракций мелкого песка. The soil profiles the Khankaiskiy Nature Reserve represent multilayer spectra of various lithological addition. The complexity of soil profiles in terms of particle-size distribution is determined by the degree of manifestation of soil and alluvial processes, lithological features of soil-forming material. Several lithological groups are distinguished by the type of texture. Dark humus gley, alluvial meadow gley soils and burozem gleyic shrouds are distinguished by a sharp differentiation of the profile by granulometric composition into an upper light and lower clay thickness. The largest content of fractions of physical clay and silt was noted throughout the profiles for these soils. Burozem typical and alluvial meadow gleyic soils that have emerged from the flood zone characterize this with a lithologically homogeneous light composition. A high content of fine sand fractions was revealed in these soils.

From the study of the characteristics of the mountain dark kastanozem in the mouth of Shar Khad in Uvur Zaisan, Bogd Khan mountain

We cut in 25.5 hectares of soil at the mouth of Shar Khad in Uvur Zaisan, Bogd Khan Uul, made morphological records, determined the soil structure, its stability, physical and chemical properties, and compared it with the soil properties of the fenced area selected as the main control parameters. In this study, we compared the structure, structural stability, physical and chemical properties of mountain dark kastanozem. For the soil structure of the study area, the proportion of 0.25-10 mm structure in the 0-8 cm layer is 5-18 %, and the structure size of less than 0.25 mm is 27 %, and the structural stability is 2-2.5 on average at 0-3 cm soil In terms of points and mechanical composition, light loam and sandy soils predominated in the 0-8 cm layer of soil, sand content increased by 48.2%, physical clay content decreased by 68.8%, and humus content decreased by 0.6% from the fenced area selected for control. As a result, the characteristics of the dark kastanozem degraded of the settled area. Богдхан уулын Өвөр Зайсангийн Шар хадны амны уулын хар хүрэн хөрсний шинж чанарыг судалсан дүн Бид Богд Хан уулын Өвөр Зайсангийн Шар хадны амны 25.5 га талбайн хөрсөнд зүсэлт хийж, морфологи бичиглэл үйлдэн, хөрсний бүтэц, түүний тогтвортой байдал, физик, химийн шинж чанарыг тодорхойлон голлох үзүүлэлтээр хяналт болгон сонгож авсан хашиж хамгаалсан талбайн хөрсний шинж чанартай харьцуулан уг судалгааг хийж гүйцэтгэв. Бид уг судалгаагаар уулын хар хүрэн хөрсний бүтэц, бүтцийн тогтвортой байдал, физик, химийн шинж чанарыг харьцуулан судлав. Судалгааны талбайн хөрсний бүтцийн хувьд 0-8 см үе давхаргад 0.25-10 мм хэмжээтэй бүтцийн эзлэх хувь 5-18 %, 0.25 мм-ээс бага хэмжээтэй бүтэц 27 %-ийг эзэлж, бүтцийн тогтвортой байдал хөрсний 0-3 см үед дунджаар 2-2.5 балл, механик бүрэлдэхүүний хувьд хөрсний 0-8 см үе давхаргад хөнгөн шавранцар механик бүрэлдэхүүн зонхилж, элсний агууламж 48.2 %-иар нэмэгдэж, физик шаврын агууламж 68.8 %-иар, ялзмагийн агууламж хяналт болгон сонгож авсан хашсан талбайнхаас 0.6 %-иар тус тус буурсан байна. Мөн хөрсний шим тэжээлийн элементүүд болох хөдөлгөөнт фосфор, солилцох калийн агууламжийн хувьд ч хашсан талбайнхаас бага байна. Дээрхи үр дүнгээс үзэхэд судалгааны талбайд тогтворжсон уулын хар хүрэн хөрсний шинж чанарт мэдэгдэхүйц өөрчлөлт орж талхагдал, доройтолд өртжээ гэж үзэх үндэстэй байна. Түлхүүр үг: Хөрсний бүтэц, хөрсний бүтцийн тогтвортой байдал, хөрсний физик шинж, хими шинж, хөрсний доройтол

INTEGRATING OF GEOPHYSICAL AND AGROCHEMICAL METHODS FOR SLOPE LANDS STUDYING

The increasing of the soil degradation of agricultural lands in Ukraine requires the improvement of their survey system. First of all, it is related to the increase of the accuracy of determinations and the density of the measurement grid. To perform these tasks, new methods are involved, primarily the geophysics ones. There are certain advantages of the integration of the studies as well as development of the substantiated rational combination of methods. Recently, promising results of the application of the magnetic susceptibility of soil to characterize the agronomic properties have been obtained. This study shows the results of the integrated application of a number of agrochemical methods and determinations of mass-specific magnetic susceptibility (MS) on the example of podzolized chernozems of Kharkiv district of Kharkiv region. We identified the possibilities of culling of values of soil characteristics from the proceeding of the results of definition of MS. The nature of the correlation between MS and humus content allows us to recommend the replacement of more expensive determination of humus content with cheaper MS. Soil magnetic susceptibility correctly reflects the spatial distribution of the main indicators of eroded lands: the humus content, and physical clay. We propose the study of sloping lands with more optimal techniques of the MS measurement of the soil as the most accessible tool.

Anthropogenic impact on grain-size distribution and agrophysical properties of soils of cultivated rice lands of Kuban

This work reviews the relation of the grain-size distribution and impact of the use of rice rotation soils on the main agrophysical indicators of soils that determine the composition and properties of soil cover of modern delta of Kuban. The regularities of dependence between the density of the matrix soil and the grain-size distribution that consist of mineral composition of alluvial soils and rocks have been identified. The trend towards increase in soil density with increase in physical clay and silt content, as well as increase in matrix soil density has been established. No significant differences in agrophysical properties of subsurface soil horizons and underlying formations have been identified. The agrophysical indicators of soils of rice fields and boharic analogues during their agricultural use have been assessed. The hydromorphic soil-forming processes did not lead to considerable changes in agrophysical properties of alluvial formations and soils involved in rice rotation.

PREDICTING DRIP IRRIGATION CONTOURS OF CHERNOZEMS OF THE STEPPE TYPE OF SOIL FORMATION

Purpose: development and testing of a method for determining the size and moisture characteristics of moisture contours formed in the southern chernozems of the steppe type of soil formation during drip irrigation. Materials and methods. Experimental studies were carried out on light, medium and heavy loamy medium thick ordinary and southern chernozems. The vertical sections of humidification zones with a system of in-contour moisture isopleths were considered. As indicators determining the contour parameters, the following are considered: the content of physical clay in the moistened soil layer, the soil density and its lowest moisture capacity. Results. In the process of studying the experimental vertical sections of soil drip moistening zones, dependences characterizing the existing functional relationships between the contour geometric parameters and the characteristics of soil, phytosoil and technological conditions of their formation were determined. On the basis of the obtained experimental dependences, a method for calculating the contours linear dimensions and graphically constructing their outlines has been developed. The proposed method for contour predicting was tested on actual data on their sizes and moisture distribution in the inner-contour space, obtained by other researchers experimentally. Comparison of the experimental and predicted contours of drip moistening testifies to their qualitative similarity both in terms of the external outline and in terms of the location of isopleths with different levels of soil moisture inside the wetted zone. The calculated value of the irrigation rate differs from the actual one by 2.2 %. Conclusions. The proposed method for predicting the sizes of moisture contours and intra-contour isopleths, formed in chernozems of the steppe type of soil formation, was developed to the level of calculations using the author's computer program. An example of approbation of the proposed method indicates its acceptability for use in the crops drip irrigation design and operational practice.

THE FERTILITY OF CHERNOZEMIC SOILS ON THE MORAINE DEPOSITS

Моренные отложения в Пензенской области образовались в результате разрушения Окско-донского ледника нижнего звена неоплейстоцена при потеплении [6, 15, 16]. Мощность основной морены может достигать ≈ 30,0 м [8, 10]. Ледниковые отложения донского горизонта по площади преобладают в западной части области. В современных физико-географических условиях они залегают в виде покрова на водоразделах и используются в агроценозе. Состав и свойства почв на моренных отложениях выделяются особенностями структурного состояния, своеобразным распределением фракций физической глины, невысоким содержанием гумуса и низким плодородием. Moraine deposits in the Penza oblast were formed as a result of the destruction of the Oka–Don glacier of the lower boundary of the neo-Pleistocene during warming [6, 15, 16]. The thickness of the main moraine can be ≈ 30.0 m [8, 10]. In terms of spacing, glacial deposits of the Don horizon predominate in the western part of the oblast. In current physical-geographical conditions, they are placed as the cover on watersheds and used in the agro-ecosystem. The composition and properties of soils on morainic deposits are special due to their structural state, peculiar distribution of physical clay fractions, low humus content and low fertility.

ХАРАКТЕР ИЗМЕНЕНИЯ ГЛУБИНЫ ЛУЧЕВИДНОГО ИЗНОСА ПРИ РАЗЛИЧНЫХ ВАРИАНТАХ АРМИРОВАНИЯ ДОЛОТООБРАЗНОЙ ОБЛАСТИ ЛЕМЕХОВ ПРИ ВСПАШКЕ ТЯЖЕЛЫХ ПОЧВ

During the operation of the plow body, a number of defects are formed on the bit-shaped part of the plowshare, one of which is xiphoid wear. Renewing the life of a given part is often reduced to eliminating such wear in various ways that are not always rational. This occurs due to insufficient knowledge of the dynamics of xiphoid wear, especially little information about plowing heavy soils. (Research purpose) The research purpose is in identifying the nature of changes in the depth of xiphoid wear in various options for reinforcing the chisel-shaped area of ploughshares when plowing heavy soils. (Materials and methods) Authors conducted research using all-metal ploughshares of domestic production in the state of delivery and reinforced according to the schemes of the location of reinforcing rollers. The reinforcement rollers were formed using E42A-UONII-13/45 electrodes designed for welding carbon steels. The thickness in the area of the ploughshare wear was determined using a calibration plate, prisms, and an indicator micrometer with an accuracy of 0.01 millimeters. To ensure the same conditions of the experiment, it was carried out in fields where the soils had the same granulometric composition, which was loam with a physical clay content of 33-38 percent. (Results and discussion) The article reveals dynamics of the development of the xiphoid wear depth depending on the operating time and technological methods of strengthening reinforcement of the chisel-shaped part of the ploughshare. The article describes the technology of strengthening reinforcement that provides the minimum wear depth with the same operating time. (Conclusions) The article presents a method for determining the depth of xiphoid wear. The proposed technology of reinforcement of ploughshares with rollers perpendicular to the field edge, with surfacing of the buried part to a length of 100 millimeters and reinforcement of the heel will increase the resource of the part by 1.3 times.