Stationary Experiment Research Articles

ПРОДУКТИВНОСТЬ ЯРОВОЙ МЯГКОЙ ПШЕНИЦЫ В СОПРЯЖЕНИИ С СОДЕРЖАНИЕМ МАКРОЭЛЕМЕНТОВ И БИОАКТИВНОСТЬЮ ПОЧВЫ НА ЧЕРНОЗЁМАХ ЮЖНЫХ СТЕПНОЙ ЗОНЫ ЮЖНОГО УРАЛА

The article is devoted to assessment of the influence of forecrops, application of mineral fertilizers on biological activity of the southern black soil and the yield of soft spring wheat. The studies were carried out in a field long-term stationary experiment in six-field crop rotations, with mono-cultivation of soft spring wheat. The object of the study was soft spring wheat put at different levels of mineral nutrition and according to different forecrops. The article presents longterm data of stationary experiment on spring soft wheat yield, biological activity of the soil under its crops, the content and consumption of macronutrients during the growing season. The vegetation periods of the studies were characterized by aridity and were divided into three groups, 13 out of 19 years were assigned to slightly arid (hydrothermal index = 0.6 and less units). Due to aridity of the growing seasons, the yield of spring soft wheat, depending on the forecrops and the nutrition background, is presented. It has been established that spring soft wheat reduces yield when cultivated in mono-seeding compared to multifield system, regardless of environmental factors. On average, for the period from 2002 to 2019, such forecrops of soft wheat as peas and millet were the best in the variant without application of mineral fertilizers. The yield of soft wheat was 0.93 and 0.90 tons per hectare, respectively. As a result of the study, an increased (in comparison with other variants of the experiment) consumption of nitrate nitrogen and potassium by permanent crops of spring soft wheat was established.

ЦИНК В СИСТЕМЕ «ПОЧВА-РАСТЕНИЕ» ПРИ ДЛИТЕЛЬНОМ ПРИМЕНЕНИИ МИНЕРАЛЬНЫХ УДОБРЕНИЙ В УСЛОВИЯХ ЮЖНОЙ ЛЕСОСТЕПИ ОМСКОЙ ОБЛАСТИ

A long-term stationary experiment was carried out on meadow-black soil in the southern forest-steppe of the Omsk region of Western Siberia, it was found that systematic application of mineral fertilizers (during six rotations of a five-field grain-fallow crop rotation) did not lead to accumulation of zinc above the APC in accordance with the Hygienic Standards GN 2.1.7.2511- 09. It has been proven that the amount of total zinc (5M HNO3 extraction) over the years of the research decreased in comparison with the initial value by 15% in a natural background and by 25% in a fertilized background due to its greater removal by plants and migration down the soil profile. Systematic application of mineral fertilizers on average over three years (2017-2019) increased the annual zinc removal by wheat plants by 16%. The content of zinc mobile form in the soil (AAB extraction, pH = 4.8) is estimated as average (2.1-2.2 mg / kg). The dependence of zinc mobile forms on acid-soluble forms was revealed, which is described by the equation y = 0.072x-0.643. The zinc content in spring wheat plants, depending on the fertilization, varied from 5.8 to 7.6 in straw and from 30.8 to 34.3 mg / kg in grain. The biological absorption coefficient was 13.1-12.8; the coefficient of biological accumulation was 14.9 -15.9, which indicates that zinc is intensively involved in the biochemical cycle of the agrocenosis during spring wheat cultivation, and its deficiency becomes a factor which limits the crop yield.

Phosphate regime of sod-podzolic soil in natural and agrophytocenoses

The phosphate regime of sod-podzolic soil (heavy loam) of Cis-Urals under natural phytocenoses (mixed forest, cereal-grass meadow) and agrophytocenoses was studied. The influence of agricultural use of arable land on phosphate regime was evaluated in the long-term stationary experiment (year of establishment – 1978) and the eastern galega (Galega orientalis L.) (year of sowing – 1988). The total content of phosphorus in soil, quantity of its organic, mineral and plant available forms were studied, the fractional composition of mineral phosphates was considered (using Ginzburg-Lebedeva method). The total content of phosphorus in the upper soil layer in all studied objects varied from 1 030 to 1 350 mg/kg. Mineral phosphorus forms prevailed over organic ones in the soil. It was found that the fractional composition of mineral phosphates was 40–62% represented by iron phosphates and 31–48% by calcium phosphates, which is due to the characteristic features of the soil-forming rock – yellow-brown non-carbonate silt drape. Aluminum phosphates amounted to 8–12%. Long-term cultivation of crops during five cycles of the eight-field crop rotation led to a significant decrease in the content of organic phosphorus in the soil. The lower content of iron phosphates (1.6–1.8 times) and the higher content (1.3–2.0 times) of calcium phosphates, available for plants, were observed in the soil of long-term experiment when compared with natural phytocenoses. The content of plant available phosphorus in soil gradually decreased from 239 to 164 mg/kg from the moment of experiment establishment to the fifth rotation. Prolonged fertilizer application (N60P60K60) resulted in the significant increase in mineral and plant available phosphorus forms content in the soil. The residual phosphorus of fertilizers was noted in the Fe-P, Ca-PI and Ca-PII fractions. Under the eastern galega the quantitative and qualitative indicators of the phosphate regime of the soil did not differ significantly from their natural analogues.

INFLUENCE OF GROWTH STIMULATORS ON SUPPLY OF CHERNOZEM WITH NITRATE NITROGEN

On the segregated chernozem of the Central Chernozem zone, in a stationary experiment, the effectiveness of various doses of complete mineral fertilizers was studied in the cultivation of spring barley. The studies were carried out in an eight-field field crop rotation. The soil of the experimental site is segregated chernozem. It was found that the use of mineral fertilizers for the main processing improved the indicators of the effective fertility of ordinary chernozem. Their combined use with foliar feeding of spring barley plants with growth stimulants reduced the content of nitrate nitrogen at low and medium doses of NPK. An increase in the concentration of nitrogen in the vegetative mass of plants with the use of fertilizers was noted. There is a clear varietal dependence in the content of mineral elements.

INFLUENCE OF SOIL TREATMENT ON THE NUMBER OF EARTHWORMS AND THE SIZE OF MICROBIAL BIOMASS UNDER THE CONDITIONS OF AGRICULTURAL INTENSIFICATION

Objective. To establish the influence of soil treatment methods on the number of earthworms and microbial biomass in dark-chestnut heavy loam soil with observance of the following crop rotation: soybean – winter wheat – corn; verify the hypothesis of the negative influence of traditional soil treatment technologies on the number of earthworms. Methods. Analytical, field, laboratory, system analysis, statistical. Results. During the studies conducted in 2018–2021 at Askanian State Agricultural Experimental Station of the Institute of Irrigated Agriculture of the NAAS, the positive influence of zero soil treatment technologies on the studied parameters versus with traditional technologies was established. A 2.5-fold increase in the number of earthworms and a 1.1-fold increase in microbial biomass was reported with zero soil treatment technologies. The interaction between soil treatment factors and cover crops in the structure of crop rotation was 23.7 %. Soil treatment technologies had a negligible influence on the size of microbial biomass — at the level of 1.4 %. The significance of the action of cover crops in crop rotation was 10.0 %. The experiment also showed a higher number of earthworms in the soil with zero soil treatment technologies with cover crops and traditional technologies for control, due to better live environment and favourable conditions for reproduction and distribution of the population depending on soil treatment technologies. Changes in the density of the soil layer 0–30 cm were within the measurement error (for zero soil treatment technologies the studied parameter was 1.23 g/cm3, for traditional — 1.24 g/cm3). Compaction of 0–20 cm soil layer with zero and traditional soil treatment technologies was reported. The content of soil organic matter by the years of studies under zero soil treatment technologies increased to 3.0 %, which is 1.2 times higher than with traditional technologies. Conclusion. Under the conditions of stationary field experiment the positive influence of zero soil treatment technologies on early changes of biological properties of soil, which were characterized by increase in number of earthworms and size of microbial biomass, has been established. The positive influence of cover crops on soil quality was determined, which was characterized by signs of biota activation in the 0–30 cm layer and improvement of biological and physical properties of the soil.

Вплив тривалих антропогенних навантажень на функціональний стан агроекосистем кукурудзи

Goal. To study the influence of the long-term application of different fertilizer systems and periodic liming on CO2 emission, the intensity of redox and biotic processes in corn agrocenoses for effective management of fertility of light-gray forest surface gleyed soils. Methods. Field research — to measure the intensity of CO2 emission, the level of redox potential, the proteolytic and general biological activity of the soil, physicochemical — determination of pNKCl, comparative-analytical — to analyze and justify the results, mathematical and statistical — to assess the reliability of research results. Results. With the use of light-gray forest surface-gleyed soils of organo-mineral (10 t/ha of manure and N65P68K68) and mineral (N105P101K101) fertilizer systems on the background of liming with a dose of CaCO3 calculated on the acid-base buffer (2.5 t/ha), in the 5th year of the aftereffect, the acidity increases, which leads to an increase in the intensity of CO2 emission, redox potential and a decrease in biotic activity during the growing season of corn. The obtained results testify to the expediency of conducting the next round of liming the light-gray forest surface gleyed soils before the beginning of each of the next 4-field rotations with the optimal dose of CaCO3 calculated on pH-buffering, which will provide a gradual shift of acid-base balance and ecological soils. Conclusions. Based on the obtained research results, a long-term stationary experiment shows the feasibility of using indicators of CO2 emission, redox potential, and biotic activity in the system of agroecological monitoring. It is established that the proposed diagnostic characteristics together with agrochemical indicators make it possible to fully assess the impact of different anthropogenic pressures on the agroecosystem.

Влияние средообразующих факторов на продуктивность озимой пшеницы

Abstract. The goal is to study the influence of the predecessor and fertilizers on the yield and quality of winter wheat grain. Methods. The studies were carried out in a long-term stationary field experiment on a gray forest medium loamy soil. Field experience, observations, accounting and generalization of research results were carried out in accordance with the methodological recommendations of B.A. Dospekhov. Statistical processing of the research results was performed using Microsoft Excel 2007 with a 95 % significance level of the results. Results. As a result of the studies, it was noted that the studied predecessors had an insignificant effect on the development of winter wheat plants in the initial phases of growth. The density of winter wheat plants during the germination period varied within the range of 314–323 psc/m2 without the use of fertilizers and 317–328 psc/m2 against the background of their application. Further growth and development of plants took place in close relationship with the studied factors. At the end of the growing season, the number of productive stems was higher on the plots, where the clover of the first year of use was used as a predecessor, both in the control (without fertilizers) and when applying mineral fertilizers. Accordingly, the yield of winter wheat grain was higher for this predecessor, averaging 35.7 c/ha for 2014–2019. Without fertilization, depending on the predecessor, 25.2–32.8 c/ha were obtained, against the background of fertilization – 34.2–39.6 c/ha of winter wheat grain. On average, over the years of research, winter wheat grain contained 10.7–14.0 % protein. Depending on the year, this indicator varied from 8.8 % to 16.8 %. At the same time, the lowest values for the protein content were obtained for the variants without the use of fertilizers. In general, the content of protein and gluten in winter wheat grain largely depended on the application of mineral fertilizers and to a small extent on the predecessor. The weight of 1000 grains, depending on these factors, changed insignificantly.

Corn productivity for grain in the short-rotary cultivation of the left bank forest-steppe depending on the fertilizer system

The study was conducted in the subzone of unstable humidification of the Forest-Steppe on chernozem typical low-humus Panfil research station NSC «Institute of Agriculture NAAS».The study was conducted in the subzone of unstable humidification of the Forest-Steppe on chernozem typical low-humus Panfil research station NSC «Institute of Agriculture NAAS».The aim of the research is to establish the influence of the structure, set and placement of field crops in a 4-field crop rotation for 100 % grain saturation on the overall productivity, yield and quality of corn grain in particular.The technology of growing crops in the experiment is generally accepted and recommended for the research area.Varieties and hybrids of agricultural crops entered into the State Register were sown in the experiment. Chemical plant protection products were used for the production of competitive commodity products of cereals.The results of studies conducted in a long-term stationary field experiment, established in 2001, to study crop rotations on typical chernozems of unstable moisture of the Left Bank Forest-Steppe, convincingly show that for highly specialized farms the most rational in this area are 4-field crop rotations. saturation with grain crops (winter wheat peas-corn for spring barley grain) using various fertilizer systems (without fertilizers), mineral (with the introduction of N60P60K60), organo-mineral (NPK + by-products of the predecessor), organic fertilizer systems (by-products of the predecessor)). The grain yield of corn depended on the fertilizer system and was in the range of 5.86–8.30 t/ha. Productivity of crop rotation area for harvesting from 1 ha of arable land with corn for grain in 4-field crop rotation was: grain – 4.54–6.29 tons, fodder units –7.48–10.47 tons; digestible protein – 0.60–0.84 tons. The economic efficiency of growing corn for grain in short-rotation crop rotation, depending on the fertilizer system, is: relatively net profit – 16.04–21.34 thousand UAH/ha, the level of profitability –112 –180 %.

Environmental evaluation of nuclide pollution rate of podzolized chernozem after long land use

At present, the development of agriculture is impossible without the use of fertilizers which provide increased soil fertility and yields as well as improve the quality of agricultural products. However, it can lead to signifcant changes in the composition, properties and formation of arable soil regimes. First of all, the negative influence of fertilizer materials on the environment is related to their chemical composition and presence of ballast substances. The maximum permissible concentrations of chemical elements in the soil must be taken into account under applying fertilizer materials for each crop. The research was conducted under the conditions of a long stationary feld experiment using different levels of mineral fertilizers of N 45P45K45, N90P90K90 and N135P135K135. . The research results reveal that different doses of mineral fertilizers have an effect on the change of the specifc activity of radioactive isotopes in the soil (226Ra, 232Th, 40K, 137Cs, 90Sr) in their long-running application (50 years). The specifc activity of radionuclides in podzolized chernozem and in winter wheat grain was established. Winter wheat plants accumulated 232Th most of all but the use of fertilizers reduced it due to biological dilution in larger mass of the crop. The absorption of radioactive nuclides by winter wheat grain after cultivation after peas and silage corn depended on fertilization varied similar to that of the clover predecessor. According to the specifc activity of radioactive nuclides in the soil and winter wheat grain, the coefcient of their biological absorption is calculated. Absorption of radionuclides by soil prevents them from moving through the profle and further penetration into groundwater. Thus, their specifc activity was two times lower at the depth of 40–60 cm than in the soil layer of 0–20 cm. This indicates that radioisotopes are fxed in the upper layers of the soil which in turn increases their entry into crop production. Key words: radioactive isotopes, radium, thorium, potassium, cesium, strontium, specifc activity of radioactive nuclides.

Biological Nitrogen Fixation and Denitrification in Rhizosphere of Potato Plants in Response to the Fertilization and Inoculation

The study aim was to evaluate the potential nitrogen fixation and denitrification in the rhizosphere soil of potato plants, crop yield and output quality in response to the different fertilization systems and the inoculation with Azospirillum brasilense 410. Field stationary experiment was conducted between 2016 and 2019 with potato in a crop rotation system on leached chernozem soil. Farmyard manure, 40 t/ha, applied prior to potatoes planting promotes nitrogen fixation (0.8–2.0 times compared to control). However, it has also affected denitrification (in 1.4–2.2 times higher compared to control). The lowest rate of mineral fertilizers used in the experiment, N40P40K40, was shown as most environmentally feasible. Under its use the increase of soil nitrogenase activity and low denitrification levels were observed. Same trends were also noted for the medium fertilizer rate, N80P80K80. The highest doses of mineral fertilizers, N120P120K120, substantially affected the denitrification process and reduced the nitrogen fixation activity (in 1.9–2.2 times). The combination of manure with the medium fertilizers rate has also resulted in high denitrification levels, while the soil nitrogen fixation activity has restored only at flowering stage. Crop inoculation with A. brasilense combined with the manure application, has not affected studied processes. However, crop inoculation after the green manure intercropping has shown the growth of nitrogenase activity. Used on the mineral fertilizers background inoculation has activated nitrogen fixation and has ensured the decrease of denitrification levels, subject to the fertilization background. High fertilizer rates have hampered the inoculation efficiency. Inoculation has promoted crop yields on unfertilized and mineral backgrounds or following green manure. Crop inoculation following organic and the organo-mineral backgrounds had no significant effect, probably due to the competition for A. brasilense from microorganisms that have created a competitive environment for A. brasilense. Despite its environmental expediency, inoculation combined with the low fertilizer doses underperforms the action of inoculation combined with the medium fertilizer rates showing the latter as the compromise between the environmental requirements and crop productivity. The use of inoculation has promoted the accumulation of starch and ascorbic acid and has contributed to the reduction of nitrate contents in the tubers of inoculated plants.

The effect of chemical agents on the productivity of crop rotations with legumes and cereals in the conditions of unstable moisture in the south of the Non-Black Soil Zone of Russia

The article summarizes the results of 1990-2012 research conducted during the stationary experiment on leached heavy loam chernozem in the Republic of Mordovia. The objects of the study are two crop rotations (grain-grass-fallow and grain-grass crop rotations) where alfalfa of the VEGA 87 variety was used as a bean component, smooth brome (Bromus inermis) Penza 1 was used as a grain component. It has been established that mineral fertilizers in grain-grass-fallow crop rotations with legumes increased productivity by 0.34-0.55, with cereals – by 0.31-0.73 tons of feed units/ha. That provided to get additional income from 1.19 to 1.40 and 1.09 to 1.47 rub/rub, respectively. Recommended doses of mineral fertilizers against soil liming by 0.5 hydrolytic acidity (h.a,) were N22-39P42K52, for grain-grass-fallow crop rotation with alfalfa and N27-71P42K52. with smooth brome. In the grain-grass crop rotation with legume and cereal components the payback of 1 kg active ingredient (a.i.) of complete mineral fertilizer was 6.13 and 6.17 kg feed units, additional income was 2.00 and 1.99 rub/rub, the productivity increased by 0.86-1.08 and 0.84-1.22 tons of feed units/ha, respectively. The payback of 1 kg of a. i. nitrogen as part of a complete mineral fertilizer in this crop rotation averaged 13.04 kg feed units versus 11.5 kg in legumes. Recommended doses of mineral fertilizers were N26-87P46K65 against the background of liming of the soil by 0.5-1.0 h. a. In crop rotation with smooth brome phosphorus-potash fertilizers should not be applied due to the low additional income (0.97-1.07 rub/rub).

The influence of local climate change on the productivity of spring cereals in the Kirov region

On the basis of long-term meteorological data and research results in a long-term stationary experiment of 1971-2020 a retrospective analysis of changes in air temperature and precipitation in the eastern region of the central climatic zone of the Kirov region was carried out and the influence of these characteristics on the dynamics of the yield of spring cereals was estimated. It has been established that the average annual air temperature during the research period was 2.4±1.0 °C. At the same time, its stable positive trend was observed at the rate of 0.39 °С /10 years. Two decades from 2001 to 2020 were recorded as the warmest for 50 years, when the temperature was 0.7...2.6 °C above climate normal. Selyaninov hydrothermal coefficient (0.7...2.1) testifies to the contrasting conditions of humidification of the vegetation periods during the research years – from drought to excessively humidified. In a long-term experiment, the yield of spring cereals increased in the row wheat – barley – oats: 2.17±0.86, 3.04±0.61, 3.39±0.65 t/ha, respectively. Strong correlations were marked between the average yield (spring wheat) and weather conditions in June: reverse with air temperature (rр = -0.735) and direct with the amount of precipitation (rр = 0.686). It has been established that the use of phosphorus fertilizers (and their aftereffect) in combination with nitrogen-potassium fertilizers weakened the influence of weather conditions on the productivity of spring wheat: the determination coefficients (R2), which reflect the portion of variability due to weather conditions, were 0.59-0.73 for the variant without fertilizers and decreased to 0.50-0.56 when applying NP3K.

Efficiency of basic tillage systems in the cultivation of barley

The effectiveness of long-term use of various basic tillage systems of dark grey forest soil in the conditions of the Northern Trans-Urals was established. Their impact on the efficiency of barley cultivation depending on the grain (spring wheat) or legume forecrop (vetch for grain) was determined. The research was carried out in a stationary experiment covering moldboard, nonmoldboard, combined, differentiated, stubble-mulch and surface systems of basic soil tillage. The experiments took place during the third–sixth rotations (1996–2018) of two grain-fallow crop rotations spread in time and space. The first crop rotation was: bare fallow – winter rye – spring wheat – spring vetch – spring barley, the second crop rotation: bare fallow – winter rye – spring wheat – spring wheat – spring barley. When cultivating barley following the legume forecrop (spring vetch), it was economically feasible to use basic tillage systems with the elements of minimization. It included non-moldboard and combined tillage with subsurface loosening by a plow with SibIME tines to a depth of 20-22 cm differentiated with stubble-mulch at 12-14 cm and disk harrowing at 10- 12 cm. These methods provided conditions for the formation of productivity close to the moldboard system and practically the same yield of barley, net income and energy efficiency coefficient. Without fertilizers, the yield was 2.97-3.03 t/ha, with the use of N40P40P40 it was 3.47-3.65 t/ha. When planting barley following wheat sown twice, the most effective was moldboard tillage system with a net income of 14.67 thousand rubles/ha without fertilizers and 22.75 thousand rubles/ha with fertilizers and energy coefficient of 2.65 and 2.75. The use of resource-saving tillage methods with repeated wheat led to a decrease in the yield of barley grain by 0.09–0.40 t/ha, and a decrease in the net income of barley cultivation compared to the legume forecrop by 31.0–44.1%.

FORMATION OF CORN PRODUCTIVITY IN CROP ROTATION DEPENDING ON LONG-TERM FERTILIZATION AND LIMING

Corn (Zea mays L.) is one of the main source of feed and food resources. The importance of this culture in the world economy continues to grow. In Ukraine corn is an export-oriented crop of universal purpose and high potential. Based on the results of research in the ninth rotation of long-term stationary experiment, it was found that in the Western Forest-Steppe in four-field crop rotation on Albic Stagnic Luvisol the highest productivity of corn 73 t . ha–1 is formed by organo-mineral fertilizing system with systematic joint application of 10 t . ha–1 manure, N65Р68К68 on the background of periodic liming with 1.0 n CaCO3 by hydrolytic acidity. It is shown that long-term unilateral application of mineral fertilizer system (more than 50 years) on acidic soil along with the accumulation of nitrogen compounds increases the acidity and content of mobile aluminum compounds, leads to blocking the activity of enzyme systems, reducing absorption and transformation of nutrients and in consequence the formation of low-yield corn at the level of control without fertilizers.

Changes in the fertility of meadow-brown bleached soil with long-term use of different fertilizer systems

The article presents the results of changes in the fertility of meadow-brown bleached soil in a long-term stationary experiment, laid down in 1941. It has been established that applying various systems of manure, lime, and mineral fertilizers in a single and double dose for 79 years improves the agrochemical soil properties. The content of organic matter in the variants of the manure-lime-mineral system with single and double doses of mineral fertilizers increased from 3.00% (control) to 3.11 and 3.21%, respectively. The phosphate regime of the soil improved when manure and lime were used together with mineral fertilizers in a doubled rate up to 137 mg/kg, and against liming with a single dose of mineral fertilizers up to 76 mg/kg, in the control variant - 15 mg/kg. Under the influence of lime and single norms of mineral fertilizers for wheat, the soil solution is deoxidized to a neutral value of 6.1, in the control variant without fertilizers the soil is subacid - 5.1. In the variant with the use of only double doses of mineral fertilizers, an increased yield of 4.8 t/ha and protein content of 13.8% in spring wheat was noted, in the control - 4.3 t/ha and 12.4%, respectively. The analysis of the correlation dependence of yield and protein per grain with a complex agrochemical property showed a strong direct relationship - r = 0.91; 0.78 respectively.

Changes in anti-deflation resistance of chernozem typical under different tillage and fertilizers

The scale wind erosion is increasing in Ukraine in connection with the arid climate and intensive agricultural land use. Deflation causes significant damage not only to the soil cover, but also to the environment. Research showed that the resistance of soils to deflation depended on their structural state. The aim of the present study was to establish the influence of different tillage systems and fertilizers on agrophysical parameters of the soil. According to the method of dry sieving according to Savvinov, the content of particles larger than 1 mm and the number of agronomically valuable particles per 1% of humus according by V. V. Medvedev were determined in the soil. The research was conducted on a stationary experiment of the M. K. Shikula Department of Soil Science and Soil Conservation in Separated subdivision of NULeS of Ukraine “Oleksandr Muzychenko Velykosnytinske Educational and Research Farm” of Fastiv district of Kyiv region. The soil of the experimental site is chernozem typical. It was found that in the variant with the application of straw, green manure and mineral fertilizers for reduced tillage, the content of particles larger than 1 mm was the highest and amounted to 75.1-77.5%. Conservation tillage systems provided a deflation-resistant soil surface, as the content of particles over 1 mm was greater than 60%. Reduced tillage together with the fertilizer variant "Straw 1.2 t / ha + N12 + N78P68K68" creates the best conditions for aggregation in a layer of 0-30 cm of chernozem typical. On non-plowing tillage, more favorable aggregation conditions were on the variant "Straw 1.2 t / ha + green manure N12 + N78P68K68". On variant with plowing, the indicators of the structural state of chernozem typical deteriorated

Impact of basic tillage systems and fertilization on agrochemical indices of soil fertility in the right bank of the Forest-Steppe of Ukraine

The paper presents the results of stationary multifactor field experiment on study of the mutual impact of various systems of soil deep and surface tillage in combination with various levels of organic and mineral fertilizers application on crop rotation performance, as well as on a number of agrochemical indicators of black soil fertility. Researches were carried out as a stationary field experiment on the experimental field of Bila Tserkva National Agrarian University in 2013-2018. During the crop rotation in all the studied tillage methods, especially mouldboardless and disking tillage, the hydrolytic acidity of the arable layer increased with increase in fertilizer rates, and the amount of bases absorbed, saturation degree, level of exchangeable calcium and magnesium cations decreased, but in most cases these changes were not significant. Systematic mouldboardless and disking tillage enhance the topsoil heterogeneity in relation to agrochemical indicators of its fertility. Heterogeneity increases with increase in the level of applied fertilizers. With the mouldboard tillage during the crop rotation period at unfertilized areas, the largest part of humus loss in the arable layer is observed in the top, and the smallest - in its bottom parts; the opposite pattern was observed on fertilized areas at the highest rate. With mouldboardless and disking tillage, directly opposite patterns were observed in comparison with mouldboard tillage. An annual application of 8 t/ha of manure + N76P64K57 stabilizes the humus state of the arable soil layer when carrying out differentiated and disking tillage in crop rotation. Fertilization rate of 12 t/ha of manure + N95P82K75 for these tillage options a significant increase in humus and total nitrogen reserves is provided.

Phosphorus fertilizer payment taking into account its long-term after-effect

When phosphorus and nitrogen fertilizers are used together, their interaction is positive. This relationship is expressed differently in different weather conditions. Its manifestation also depends on elements of culture cultivation technology. In order to optimize phosphorus nutrition, pre-determined doses of phosphorus are offered, sometimes highly overestimated, which should have a long-term follow-up. To control the content of mobile phosphorus, doses of phosphorus have been developed, which can increase the index of plant availability with this element by 10 mg/kg. In a stationary experiment at the Central Experimental Field of the Kurgan NIISH, the effect of three doses of phosphorus-free nitrogen and combined with phosphorus fertilizer for 25 years and the further follow-up of phosphorus was evaluated. Phosphorus fertiliser was added for 25 years on the background of nitrogen in a dose of P40. Once the phosphorus fertilizer is discontinued, the duration of its follow-up is now 24 years.

Environmental aspects of long-term use of mineral fertilizers on leached blacksoil of the Western Ciscaucasia

The research purpose consists in studying the effect of long-term use of mineral fertilizers on changes in the fertility of leached blacksoil (Grey-Luvic Chernozems) of the Western Ciscaucasia. The studies were conducted in the framework of the stationary field experiment of the Department of Agrochemistry of the Kuban State Agrarian University, founded in 1981 and occupied by crops of 11-field grain-grass-row crop rotation. Over the period of 1981-2019 years, N950P910K670, N1900P1820K1340 and N2850P2730K2010 were applied on contrasting variants with single, double and triple norms of mineral fertilizers, respectively. Comparison backgrounds are represented with initial indicators prior to the station establishment and with the control variant without fertilizers. The fertilizer system used in crop rotation supports optimal parameters of leached blacksoil fertility (pHH 2 O= 6.41-6.50; humus content – 3.50-3.58%; nitrogen content – 21.8-27.7 mg NO3/kg and 13.0-16.0 mg NH4/kg; mobile phosphorus – 155-170 mg P2O5/kg; exchange potassium – 255-266 mg κ2O/kg) and improves the physical properties of soil. At the same time, during the 38-year period of annual application of mineral fertilizers, soil acidification was recorded (hydrolytic acidity increased by 0.51-0.93 mg-eq/100 g; pHKCl values decreased by 0.30-0.38 units; pHH 2 O – by 1.20-1.33 units), while the amount of absorbed bases decreased by 10.27-12.27 mg-eq/100 g, cation exchange capacity – by 9.76-11.34 mg-eq/100 g, and the degree of soil saturation with bases – by 2.66-4.00%. Periodic monitoring of changes in agrochemical and agrophysical indicators is necessary to reduce the risks of degradation and preserve the fertility of leached blacksoil.

Influence of Different Types of Land Use on Prokaryotic Communities and Organic Matter Stabilization in Soddy-Podzolic Soil

The influence of crop rotation with different saturation with legumes and continuous grain crops (winter rye and spring barley) on the structure of prokaryotic communities and preservation of soil organic matter has been studied in a long-term stationary experiment (1977–2018) on a soddy-podzolic soil (Eutric Albic Retisol (Abruptic, Loamic, Cutanic)) of Perm oblast. Permanent black fallow and unmanaged fallow were used as reference standards. Minimum values of the coefficients of mineralization (0.37) and pedotrophicity (0.28) calculated on the basis of direct counting of microbial colonies cultivated on standard nutrient media (MPA, SAA, and SA) have been found in the unmanaged fallow soil, and maximum values of these coefficients (1.97 and 1.30, respectively) were found in the black fallow soil. Inverse relationships were found between the Corg content in the soil and the mineralization coefficient (r = –0.67; p crop rotation (0–28.6–42.9% of legumes) > continuous grain crop > permanent black fallow, In the cultivated and black fallow soils, along with general decrease in the organic matte stock, its lability increased as evidenced by the Cha : Cfa ratio (0.55–0.79), which were lower than in the unmanaged fallow soil (0.96). The closest negative correlation (r = –0.81; p < 0.001) was observed between the mineralization coefficient and the Cha : Cfa ratio. It has been also shown that different uses of soddy-podzolic soil were accompanied by structural rearrangements of the actinomycetal complex selected as a model group of soil microorganisms. In particular, regular mechanical tillage and application of mineral fertilizers (N60P30K60) contributed to an increase in the species spectrum of streptomyces, a change in the frequency of occurrence and relative abundance of individual sections and series, and a change in dominant forms. The results of this study demonstrated the possibility of using microbiological indicators as biomarkers of the state of soil organic matter.