Expanded Reproduction of Chernozem Fertility in Biological Agriculture

The current stage of development of zonal farming systems in the Central Black Earth region involves the creation of balanced, highly productive, and sustainable agricultural landscapes, maximally adapted to the natural conditions of the region and ensuring the preservation and improvement of soil fertility. The solution to the problem of reproduction of soil fertility in traditional agriculture is associated with the use of a large number of energy-intensive resources and, first of all, irreplaceable ones. However, the level and direction of soil/biological processes are not sufficiently taken into account, whereas they to a certain extent ensure the reproduction of soil fertility. In this regard, the problem of the formation of the scientific foundations of the reproduction of soil fertility through the integrated use of methods of biologization of agriculture in the Central Black Earth Region and the activation on this basis of the soil/biological factor in the long-used chernozems acquires special importance. The purpose of the study is to review the changes in soil fertility indicators in conditions of biological agriculture. The paper presents the results of a study to determine changes in soil fertility indicators in typical chernozem of the Belgorod region (Russia) in a field experiment with various technologies of crop cultivation. The study demonstrates the regularities of the transformation of the fertility of chernozem. In terms of its fertilizing efficiency, compost in the applied norm turned out to be equivalent to a half dose of mineral fertilizers since both variants under consideration provided equivalent increases in the corn yield. The full dose of mineral fertilizers on the background of organic matter turned out to be excessive since its introduction did not contribute to a reliable increase in corn productivity.

Bioproductive сapacity of typical chernozem in the Left-Bank Forest-Steppe of Ukraine under favorable humid conditions

The article presents the results of research on the assessment of modern climate change and the impact of weather conditions on the yield of main field crops when using different feeding systems and tillage. It was established that during 1991-2020 the average annual air temperature in the region increased by 1,1oC, and the annual precipitation decreased by 5%. Under such conditions, the frequency of recurrence of highly and moderately arid conditions of the growing season increased from 47% in 1961-1990 to 61% in 1991-2020, however the probability of forming a sufficient moisture supply decreased by half. Based on the results of the Climate Water Balance (CWB) assessment, it was specified that in the western part of the Left-Bank Forest-Steppe, according to average long-term data a negative WBC has been formed since June, and by the end of August its deficit reaches over 140 mm or 1,400 m3 / ha. In general, by the end of the period for 1991-2020, the deficit of WBC increased by 82 mm. Based on the information database made on the results of long-term stationary field experiment at Poltava Research Station of the Institute of Pig Farming and Agroindustrial Production of NAAS, the yield potential of main crops and the productivity of typical chernozem subject to the optimization of crop rotation and nutrient and water-air regimes, were evaluated. It was determined that optimization of crop rotations increases plant productivity by 19%, fertilizer systems - by 19-36%, irrigation - by 94%, irrigation and fertilization - by 130-153%, and a comprehensive combination of all agronomic measures - by 200% and more. It was also established that the total productivity of crop rotation under different systems of basic tillage remains virtually unchanged and enables to obtain average by year 3.6-3.8 t kd / ha against the background of natural soil fertility. From the organic fertilizer systems, the efficiency of using crop by-products as fertilizers is 10% higher than using manure and practically does not concede to organomineral fertilizer systems. As a result of research it was found that in the region in recent decades there is a tendency of deteriorating growing conditions of main field crops, which is reflected in the formation of low yields and poorer crop rotation productivity, significant variation of these factors in terms of weather, especially when having high soil fertility.

Ecological Assessment of Sulfur Content in Agroecosystems of the Central Black Earth Region of Russia

Studies were carried out on the territory of the steppe and forest-steppe zones of the Central Black Earth Region of the Russian Federation. The objects of research were the soil of nature reserves and arable chernozems that were not touched by agricultural activity, typical and common, the vegetation cover of natural biocenoses and agroecosystems, and organic fertilizers. The studies found that the background content of mobile sulfur in virgin soils is at a low level: 2.31 mg/kg - in a typical chernozem and 1.83 mg/kg - in an ordinary chernozem. According to agrochemical monitoring of arable soils carried out during 2015-2018, an increase in the weighted average content of mobile sulfur by 0.7 mg/kg to 3.3 mg/kg was established, compared to 2005-2009. However, the proportion of soils low on this element remains quite high - 90.3%. The main source of sulfur supply to the soils of agroecosystems (7.52 kg/ha) are organic fertilizers, the doses of which in 2015-2018 increased to 8.1 tons/ha. The average sulfur content in the steppe mixture of herbs of reserves is 0.3-0.4 mg/kg. The highest sulfur content among perennial legumes is clover (0.61%) and alfalfa (0.60%), and among legumes - soybeans, containing 0.34% of the element in grain and 0.21% - in straw.

DYNAMICS OF HUMUS RESERVES AND FORECAST OF CARBON-INVESTING POTENTIAL OF ZONAL SOILS OF THE REPUBLIC OF TATARSTAN

The article analyzes the results of statistical processing of morphometric and agrochemical indicators of zonal soils of the Republic of Tatarstan based on the accumulated information of large-scale soil studies. The boundaries of genetic horizons are examined, the content of humus and its reserves within the limits of heavy loamy and clay varieties of arable soil subtypes is estimated. Arithmetic averages allow us to generalize the humus content in soils. So, in the series of sod-podzolic soils – light gray forest-gray forest – dark gray forest-podzolic chernozems – leached chernozems-typical soils in a layer of 0-30 cm on average contains 2,20; 2,58; 3,76; 4,76; 6,8; 7,6; 7,2 % humus. The observed patterns of humus accumulation in soils are also preserved in the distribution of its reserves – 85; 97; 140; 162; 233; 257; 240 tons per he-1. It is proposed to characterize the general population along the boundaries of typical values that fit into the 50% confidence interval to assess the overall range of spatial variability of humus indicators. The upper limit of the typicity will correspond to the greatest accumulation of humus with a combination of local features of soil formation factors and can serve as a guide for predicting carbon sequestration in the soils of this region. Accordingly, the carbon-sequestering potential of sod-podzolic soil and typical chernozem is-20 tons per he-1, light gray forest soil-22 tons per he-1, gray forest soil and leached chernozem-27 tons per he-1, the highest values in dark gray forest soil are more than 30 tons per he-1

Morphological and physiological-biochemical variability of spore-forming bacteria isolated from the agrocoenosis of winter wheat

From an agrocoenosis of winter wheat (Triticum aestivum L.; phylloplane and rhizosphere of the root system; typical chernozem, soil column measuring up to 40 cm), using the classical microbiological methods, we had isolated soil bacteria and characterized them according to the morphological features as representatives of Gram-positive and spore-forming bacteria of Bacillus sp. genus. In the earing-swelling phase of grain, the screening studies found non-pigmented forms of colonies of bacterial isolates, 19 of which were classified to colonial-morphological diversity of R-type with the diameter of 7 to 13 mm. The analysis of physiological condition of cells of populations of soil isolates revealed technologic specificity according to parameters of spore formation in different conditions and incubation time (up to 48–72 h). We observed 90.0% of free spores in axenic cultures as early as after 72 h of cultivation and no more than 10.0% of prospores in the studied monoisolates with stable morphologic traits. Isolates Н10 and Н45 demonstrated the ability to grow in higher cultivation temperatures (+37…+40 °С). According to environmental рН, isolates were able to grow in рН ranging 4.5–8.0. Differential diagnostic testing revealed that as the source of carbon, with formation of acid, soil isolates used arabinose, xylose, mannitol, glucose, galactose, fructose, maltose, sorbitol, glycerin, dextrin, starch, rhamnose and dulcite (with development of alkaline). There was observed active use of mineral forms of nitrogen: ammonium salt and nitrates, aminoacids and proteins. The isolates hydrolyzed casein, gelatin, starch, and litmus was being reduced in the young during growth in milk with litmus. They also exerted catalase activity and were oxidase-positive. Biochemical testing using API test system determined that the studied isolated bacteria differed by a range of fermentation carbohydrates, reduction of nitrates. In the conditions of submerged fermentation, isolates Н38 and Н40 grew in heightened temperature ranges of cultivation (40 °С) for 48 h (according to fact of spore development). Therefore, according to the key morphologic and biochemical traits, strains Н3, Н10, Н13, Н36, Н38, Н40, Н43, Н45 were similar to such of reference strain B. subtilis 8A, and were identified to Bacillus sp., species B. subtilis.

Effect of fertilizer doses on bioenergy productivity of sugar sorghum

It was found that sugar sorghum for growing in conditions of insufficient moisture on typical chernozem responds positively to the application of mineral fertilizers. The use of fertilizers increased the accumulation of sugars in plant stems in the phase of wax ripeness by 0.5−2.3%, biomass yield by 3.0−18.1 t/ha, bioethanol yield by 0.2−1.1 t/ha, solid fuel by 1.2−6.8 t/ha, total energy yield by 24−135 GJ/ha. The maximum bioenergy productivity of sugar sorghum was reached by growing hybrid ‘Nektarnyi’ and applying N120P120K120. The yield of bioethanol was 3.7 t/ha, solid fuel 22.2 t/ha, total energy yield 446 GJ/ha with excess of control without fertilizers by 1.1 t/ha, 6.8 t/ha and 135 GJ/ha, respectively.

Agrophysical properties of soil and yield of spring barley for various predecessors and mineral fertilizers in the Central Black Earth Region

The research is devoted to the study of the influence of precursors and mineral fertilizers, applied in various doses, on the agrophysical properties of the soil, the value of the grain yield of spring barley in the soil and climatic conditions of the Central Black Earth region. The field experiment was based on the long-term hospital of Belgorod State Agrarian University named after V. Ya. Gorin. As an object, the variety of spring barley Knyazhich, recommended for the region, was chosen. The soil of the experimental plot is typical chernozem, medium loamy granulometric composition on loess-like loam. The experiment scheme (4×4) provided for the study of four gradations of factor A (predecessors: corn for grain - control, sunflower, sugar beet, soybeans) and factor B (doses of mineral fertilizers: N10P10K10 - control, N30P30K30, N50P50K50, N70P70K70). Growth and development of spring barley plants in 2018-2020 took place in meteorological conditions characterized as arid with a predominance of elevated temperatures and insufficient precipitation during the critical phases of plant vegetation. The results of field experiments established that the water and agrophysical properties (density and structural-aggregate composition) of the soil under the influence of previous crops approached the optimal values and changed insignificantly. Increased doses of mineral fertilizers had a positive effect on the value of the yield of barley grain according to the studied predecessors. The highest grain yield over the years of research was obtained at high N50P50K50 and intensive N70P70K70 backgrounds for the predecessors of soybeans and sugar beets and amounted to 5.48 and 5.03 t/ha and 5.33 and 5.32 t/ha, respectively. This was higher than the control of corn for grain 0.82 and 0.37 t/ha and 0.62 and 0.61 t/ha, while for sunflower it decreased to 4.06 and 4.71 t/ha and was at the level with the control.

Changes in agrophysical properties of typical type of black type under the influence of fertilizer application and soil treatment

The solution to the problem of increasing the production of agricultural products largely depends on the correct assessment of the level of fertility and cultivation of the soil, a clear understanding of its main indicators optimal for cultivated plants and the use of an effective soil fertility management system on this basis. The goal is to determine the effect of the use of systems of basic tillage and fertilization in grain-tilled crop rotation on changes in soil density in the agrophytocenosis of winter wheat. Methods: The soil density was determined with M. Kachinsky cylinders in the arable layer of 0–10, 10–20, 20–30 sm. The results of stationary studies of the effect of prolonged (2012–2019) application of three options deep coarse-silty-medium loamy in ten-field grain-row crop rotation of the right-bank forest-steppe for its agrophysical indicators. It has been established that the variant of dump-dump-free tillage in the crop rotation creates the best agrophysical conditions for the fertility of typical chernozem. The use of shallow moldboard-free tillage led to a significant increase in soil density (on average by 0,02–0,04 g/sm3) compared to the control. The use of shallow moldboard-free tillage led to a significant decrease in the total porosity by 2,2% in comparison with differentiated and moldboard-free tillage.

Protective afforestation in agroforestry landscapes of the Middle Don basin

The use of forest reclamation facilities to transform the landscapes of the Middle Don basin of the European part of Russia is an important aspect in improving the natural conditions of agricultural territories. In the Central Black Earth Region, they occupy an area of 600000 hectares and form the ecological framework of forest agrarian landscapes. The purpose of our research is to establish the optimal conditions for the growth and reforestation efficiency of protective plantations in different conditions. Modern methods and approaches were used for forestry and land reclamation assessment of forest belts. In artificial linear plantings, the biometric indicators of growth and safety in fast-growing species are most pronounced at the initial density of creation and 3334 pcs/ha. The best companions for joint cultivation of English oak are Norway maple and yellow acacia. In the conditions of typical chernozem, the highest values for the growth of rocks are noted. In winter, protective plantations accumulate snow water reserves of 435-430 m3/ha, which makes it possible to form an additional yield of grain crops by 320-430 kg/ha in the strip zones.