Fertilizer Components Research Articles

Effects of different returning method combined with decomposer on decomposition of organic components of straw and soil fertility

In view of the problems of low straw decomposition rates and reduced soil fertility in southern Liaoning, China, we investigated the effects of no-tillage mode (NT), deep loosening + deep rotary tillage mode (PT), rotary tillage mode (RT) and the addition of decomposing agent (the next is called a decomposer) (NT + S, PT + S, RT + S) on the decomposition proportion of straw, respectively, by using the nylon net bag method in combination with 365-day field plot experiments. The decomposition rules of cellulose, hemicellulose and lignin as well as the dynamics of soil organic carbon (SOC), soil microbial biomass carbon (MBC) and soil dissolved organic carbon (DOC) in straw returned to the field for 15, 35, 55, 75, 95, 145 and 365 days were analyzed. The results showed that in the short term, the decomposition of straw was better in both the rotray tillage and deep loosening + deep rotary modes than in the no-tillage mode, and the addition of decomposer significantly promoted the decomposition of straw and the release of carbon from straw, among them, the RT + S treatment had the highest straw decomposition proportion and carbon release proportion in all sampling periods. After a one year experimental cycle, the RT + S treatment showed the highest proportion of cellulose, hemicellulose and lignin decomposition with 35.49%, 84.23% and 85.50%, respectively, and soil SOC, MBC and DOC contents were also higher than the other treatments with an increase of 2.30 g kg−1, 14.22 mg kg−1 and 25.10 mg kg−1, respectively, compared to the pre-experimental soil. Our results show that in the short term, to accelerate the decomposition rate of returned straw and increase the content of various forms of carbon in soil, rotary tillage can be used to return the straw to the field, while also spraying straw decomposer on its surface. This experiment used a new straw decomposer rich in a variety of microorganisms, combined with the comparison of a variety of straw return modes, and in-depth study of straw decomposition effects of cellulose, hemicellulose and lignin. Thus, a scheme that can effectively improve the decomposition rate of straw and the content of various forms of organic carbon in soil within a short period of time was explored to provide theoretical support for the southern Liaoning.

Effect of supplemental trace minerals on standard and novel measures of bull fertility

Two studies were conducted to evaluate the effects of trace mineral supplementation on traditional and novel measures of bull fertility. In Experiment 1, 37 mature bulls received one of three dietary supplements daily for 71 d: 1) Supplement without Cu, Zn, and Mn (CON); 2) Supplement with Cu, Zn, and Mn sulfate (SULF); and 3) Supplement with basic Cu chloride, and Zn and Mn hydroxychloride (CHLR). In Experiment 2, 128 Angus or Angus-Hereford bull calves were maintained on a growing diet for 75 d (year 1) or 119 d (year 2) in Calan gate equipped pens without mineral supplementation. Bulls (n = 32 head/treatment) received one of four trace mineral supplements daily for 84 d: 1) Zn with no Cu (ZN), 2) Cu with no Zn (CU), 3) Cu and Zn (ZNCU), or 4) no Cu or Zn (CON). Bull fertility measures included a breeding soundness evaluation (BSE) and novel fertility measures conducted using flow cytometry. In mature bulls, final liver Zn concentration was positively correlated (P = 0.02) with sperm concentration (r = 0.31) and tended (P = 0.06) to be negatively correlated with acrosome damage (r = −0.39). Peripubertal bulls receiving ZNCU had greater ADG than bulls in the CU group (P = 0.05). Each BSE and novel fertility component improved from Day 0–84 in peripubertal bulls and were not affected (P > 0.10) by mineral supplementation. Bulls that received no supplement (CON) had greater (P < 0.01) percentage of sperm with distal midpiece reflex (6.9 vs 4.0% for CON and TM supplement, respectively) and Dag or Dag-like defect (2.6 vs 1.4% for CON and TM supplement, respectively) in their ejaculates. Sperm viability after 30 min of incubation were not affected by trace mineral supplementation, but after 3 h incubation, sperm viability tended to differ (P = 0.06) between treatments and tended to be less for CON bulls (48.5%) compared to ZNCU bulls (55.1%). Among contrast comparisons, trace mineral supplemented bulls had greater (P < 0.05) percentage of viable sperm at 3 h post collection and reactive oxygen resistant sperm than CON bulls. Addition of Zn to trace mineral containing Cu (ZNCU) improved (P < 0.05) percentage of sperm in the ejaculate with high mitochondrial energy potential and viable sperm with intact acrosome membrane. In summary, it appears the homeostasis mechanisms for bull trace mineral maintenance are extremely efficient and mineral supplementation of mature and peripubertal bulls did not have major improvements in any laboratory or chute-side measures of bull fertility, however bulls exposed to breeding or in environments with diet antagonists might respond differently.

High efficient removal of phosphate in aqueous solution by eco-friendly materials

The efficiency of phosphate removal in aqueous solution by CaO, Ca(OH)2 and CaCO3 has been studied in this work. Batch of experiments conducted with the initial phosphate concentrations from 5 to 1000 ppm have shown that CaCO3 could be applied for phosphate removal at low concentration with the maximum phosphate removal capacity at 4.0 mg/g. In contrast, the highest phosphate removal capacity of CaO and Ca(OH)2 was 287.36 mg/g and 235.21 mg/g at initial concentration of 500 ppm, and phosphate removal rate was 85% and 97% at initial concentration of 5 ppm. Crystalline hydroxylapatite was detected in the precipitate by XRD analysis. The molar ratio of P in the precipitate and Ca in the materials (CaO and Ca(OH)2) was 0.52 and 0.56 at initial concentration of 500 ppm, compared to P/Ca molar ratio of 0.6 in hydroxylapatite. Moreover, hydroxylapatite is the main component of fertilizer that can be applied for agriculture.

EFFECT OF FERTILIZATION AND PLANT SPACING ON YIELD AND CONTENT OF FLAVONOIDS IN FIREWEED HERB (Epilobii herba)

Fireweed (Epilobium angustifolium L.) is a quite common species in our country. However, in order to obtain larger quantities of high quality E. angustifolia herb, it is necessary to introduce it into cultivation. The study covered four-year field experiment (2013–2016). The aim of the study was to investigate the fireweed reaction to the impact of various levels of mineral fertilization and spacing. It has been shown that the increased amount of fertilizer components at the level of 60 N, 70 P2O5 and 100 K2O kg · ha–1 stimulated vegetative growth and had a positive effect on yielding. The highest biological efficiency of the plantation was found at the population density resulting from 45 × 30 cm spacing. Increasing the dose of mineral fertilization and increasing the plant spacing did not result in statistically proven impact on the quality of the raw material (flavonoid content).

POTENTIAL IMPACT OF THE IMPLEMENTATION OF THE NEW GREEN DEAL IN THE FIELD OF MINERAL FERTILIZATION ON THE YIELD OF MAIN AGRICULTURAL CROPS

The aim of the article is to estimate the impact of reducing the consumption of mineral fertilizers resulting from the New Green Deal assumptions on the yields of major crops in the 2030 perspective. The material for analysis was statistical data from the CSO and FAO. The collected data was processed dynamically by using trend analyzes and Pearson linear correlation. Maintaining the current trend of increasing the dose of NPK mineral fertilization will allow the use of crop production potential in Poland. On the other hand, the introduction of the NGD assumptions may result in a stagnation of crop yield at the current level. However, in relation to the scenario assuming the continuation of the current upward trend, these yields will be much lower. Reducing mineral fertilization introduced by means of an administrative decision without taking the principles of rational management of fertilizer components into consideration may have negative environmental consequences.

Effect of Low Zeolite Doses on Plants and Soil Physicochemical Properties.

Thousands of tons of zeolitic materials are used yearly as soil conditioners and components of slow-release fertilizers. A positive influence of application of zeolites on plant growth has been frequently observed. Because zeolites have extremely large cation exchange capacity, surface area, porosity and water holding capacity, a paradigm has aroused that increasing plant growth is caused by a long-lasting improvement of soil physicochemical properties by zeolites. In the first year of our field experiment performed on a poor soil with zeolite rates from 1 to 8 t/ha and N fertilization, an increase in spring wheat yield was observed. Any effect on soil cation exchange capacity (CEC), surface area (S), pH-dependent surface charge (Qv), mesoporosity, water holding capacity and plant available water (PAW) was noted. This positive effect of zeolite on plants could be due to extra nutrients supplied by the mineral (primarily potassium—1 ton of the studied zeolite contained around 15 kg of exchangeable potassium). In the second year of the experiment (NPK treatment on previously zeolitized soil), the zeolite presence did not impact plant yield. No long-term effect of the zeolite on plants was observed in the third year after soil zeolitization, when, as in the first year, only N fertilization was applied. That there were no significant changes in the above-mentioned physicochemical properties of the field soil after the addition of zeolite was most likely due to high dilution of the mineral in the soil (8 t/ha zeolite is only ~0.35% of the soil mass in the root zone). To determine how much zeolite is needed to improve soil physicochemical properties, much higher zeolite rates than those applied in the field were studied in the laboratory. The latter studies showed that CEC and S increased proportionally to the zeolite percentage in the soil. The Qv of the zeolite was lower than that of the soil, so a decrease in soil variable charge was observed due to zeolite addition. Surprisingly, a slight increase in PAW, even at the largest zeolite dose (from 9.5% for the control soil to 13% for a mixture of 40 g zeolite and 100 g soil), was observed. It resulted from small alterations of the soil macrostructure: although the input of small zeolite pores was seen in pore size distributions, the larger pores responsible for the storage of PAW were almost not affected by the zeolite addition.

STATE OF WASTEWATER TREATMENT TECHNOLOGIES IN UKRAINE AND THE WORLD

In sewage treatment plants, sludge is formed during wastewater treatment, in addition to treated water. They are dumped on silt sites, which occupy large areas and almost all overcrowding. The content of large amounts of minerals and toxic substances in sediments leads to the deterioration of underwater waters and land, which in turn leads to the deterioration of ecology and life in Ukraine. An urgent task in Ukraine is to create a comprehensive processing of sludge, which includes economic, technological, social and environmental aspects.&#x0D; The main methods of sludge disposal are use in agriculture, landfilling, incineration and dumping into the sea or ocean. The country is gradually trying to abandon the burial. European Union countries also process sludge aerobically and anaerobically. During these processes, components of organo-mineral fertilizers are created that can be used in agriculture. As fertilizers, sludge is composted, stabilized and pasteurized. Combustion of sludge allows to obtain a substitute for coal and oil. To increase the heat of combustion and improve combustion parameters to sludge sludge add coal, biomass. Low-temperature pyrolysis of sewage sludge and household waste, which allows to obtain "crude oil". One of the methods is processing in biogas plants to obtain both biogas and environmentally friendly fertilizers. To increase the efficiency of treatment and reduction of sludge disposal of used stagnation-ments vermiculture.&#x0D; Analysis of the literature allows us to conclude that there are methods of disposal of sludge, which have become widespread in various countries around the world, such as fertilizers, alternative fuels, landfills and others. When disposing of sludge, it is possible to produce biogas, electricity and heat, which reduces energy costs for the process.

Phosphogypsum Recycling: A Review of Environmental Issues, Current Trends, and Prospects

The problem of recycling and storage of phosphogypsum is topical for many countries around the world, as it is associated with environmental problems of pollution of water bodies, land, and atmosphere. Therefore, this paper analyzes the directions of phosphogypsum recycling and possible alternatives to its use. The main disadvantages of the existing methods of phosphogypsum processing were identified and trends in this waste management were also considered. Through the VOSviewer programme, a visualization of cluster interconnections was carried out in research publications of various fields of phosphogypsum utilization. Five clusters were formed: a red cluster—phosphogypsum recycling in the construction industry; green cluster—radiation pollution problem of phosphogypsum and phosphate fertilizers; yellow cluster—monitoring migration of phosphogypsum components in the ecosystem, with the mobile forms of heavy metals and their inflow into aquifers from phosphogypsum dumps; blue cluster—use of phosphogypsum in agriculture as an ameliorant and a component of fertilizer; and a purple cluster—the impact of phosphogypsum on microorganisms, particularly in bioremediation processes. Under the proposed integrated biochemical approach, the use of various bioprocesses of phosphogypsum recovery from waste dumps and implementation of new biotechnological solutions for processing phosphorus raw materials are presented.

Male mating behaviour and fertility of layer breeders in natural mating colony cages: LED light environmental effects

Natural mating colony cages for parent-stock layer breeders, instead of conventional cages with artificial insemination, have been widely adopted by many commercial farms in China. However, the fertility rate of this system varies greatly among different cage tiers. We speculated that the difference in fertility rate might be caused by uneven illumination because vision appears to play a central role in birds’ behaviour, including mating. The objectives of this study were to investigate the effects of 4 LED light colours (white: WL, red: RL, yellow-orange: YO, and blue-green: BG), each at 2 light intensities (10 lx, 25 lx), on mating frequency and fertility for layer breeders in natural mating colony cages. A total of 32 identical cages were involved in the 8 treatments, with 4 replicates for each treatment and 5 males and 45 females per cage. The results showed significant effects of age, light colour, light intensity and colour-intensity interaction on the frequency of mating behaviour, integrity of matings and fertility. Overall, flocks treated with WL and RL and a higher light intensity during the laying period showed more frequent mating behaviour, a larger proportion of relatively complete matings and a higher fertility. All components of mating behaviour and fertility declined from 30 wks to 50 wks of age, but no significant correlation was found between fertility and mating behaviour. In summary, the results of this study illustrate that differences in LED light colour and light intensity influenced the mating behaviour and fertility of layer breeders. WL and RL and a higher light intensity can increase the frequency of mating behaviour, the proportion of complete matings and fertility. No significant correlation was found between fertility and mating behaviour. Such knowledge can help to understand mating behaviour in natural mating colony cages and provide a basis for optimization of the light environment.

EFFECT OF WATER ACIDITY ON THE LEACHING OF FERTILIZER COMPONENTS IN UMUAHIA AGRICULTURAL SOILS

The South-Eastern Nigeria has heavy annual rainfall and at riskof leaching by acid rain hence there is a strong need to study the acidity of the leaching water from this zone as to determine it’s effect on the fertilizer components applied to the soil as soil and water pH affect nutrient retention. The study was therefore conducted to determine the effect of the acidity of water on the leaching of fertilizer components on application to agricultural soils in Umuahia one of the cities in the South-East. Agricultural soil was collected from Umudike in Umuahia and designated as Umuahia Agricultural Soil(UAS).The soil was characterized to determine texture, gravel, pH, organic matter and carbon, exchangeable acidity and cations, available phosphorus, potassium, calcium, sodium, magnesium and percentage nitrogen using their various methods of analysis. The characterization was followed by the leaching tube experiments whereby the soil samples were leached with carbonated water of different pH levels ranging from pH of 4 to 6.5 and also with rainwater with pH of 6.8 using ten tubes five with fertilizer and five without fertilizer which served as the control experiment. The leachates were collected and analysed for the concentrations of sodium,potassium,calcium and the other ions . The results of the textural classification showed the soil as sandy-clay, and that of physicochemical analysis showed organic matter and carbon as 3.82 ± 0.13 and 2.21±0.00 % respectively, nitrogen as 0.26 ± 0.11 %. The leaching tube experiment showed sodium ions as 0.19 ± 0.11 me/100g, 0.19 ± 1.10 me/100g, 0.28± 1.02 me/100g, 0.29 ±0.11 me/100g and 0.38 ±0.12 me/100g at pH of 4, 5, 6, 6.5 and rain respectively for soils with fertilizer while that of potassium ions showed 3.76 ±0.02 me/100g, 3.61 0.02 me/100g, 3.54 0.02 me/100g at pH of 5, 6 and 6.5 respectively. The soils without fertilizer showed 0.09 ± 0.01 me/100g for both Na+ and K+ at the different pH levels. Soils with fertilizers leached more ions than the soils without fertilizers. From the results, it could be inferred that the leaching of fertilizer components in the soils differed with the influence of the acidity of leaching water. Therefore, fertilizer application should be based on the acidity level of the leaching water or rain.

МОНТМОРИЛЛОНИТ КАК ПЕРСПЕКТИВНЫЙ КОМПОЗИТНЫЙ МИНЕРАЛ ДЛЯ СОЗДАНИЯ СОВРЕМЕННЫХ УДОБРЕНИЙ ПРОЛОНГИРОВАННОГО ДЕЙСТВИЯ

использования новых удобрений пролонгированного и контролируемого действия.В данной статье приводятся варианты использования монтмориллонита в качествесоставного компонента современных азотных удобрений с контролируемыми свойствамии результаты изучения минеральных трансформаций в процессе механохимической активации при различных параметрах. Основная цель работы заключаласьв оценке механизмов активации монтмориллонитакак ингибитора азотсодержащих композитных продуктов для создания удобрений пролонгированного действия. Методы: механохимическая активация в планетарной и кольцевой мельницах, рентгенодифракционный анализ, сканирующая электронная микроскопия, инфракрасная спектроскопия, дифференциальный термический анализ. Выводы. Доля интеркалированной мочевины в монтмориллоните(для смесей M1N1) изменяется в пределах 22,3…23,2% при активации в планетарной мельнице в течении 3, 8 или 11 минут. Максимальная степень интеркаляции 23,2% была достигнута при активации в течении 3 минут. После 11-минутной операции около 40…50% агрегированных глинистых частиц покрываются внешней оболочкой избыточной мочевины толщиной до 2,5 мкм. Доля интеркалированной мочевины в монтмориллоните изменяется с 23,2 до 21,6% по мере увеличения времени активации с 30 до 120 минут в кольцевой мельнице. По мере увеличения времени активации образуются микрокристаллиты мочевины на поверхности минеральных частиц.Минеральные продукты, полученные методом активации в планетарной или кольцевой мельницах, могут использоваться как удобрения пролонгированного действия с несколькими полезными функциями. Композиты, синтезированные при 11-минутной или 120-минутной работе планетарной или кольцевой мельниц, соответственно, характеризуются двумя типами азота. Изначально удобрения будут высвобождать нутриенты с высокой скоростью из внешней пленки, состоящей из мочевины, после чего будет расходоваться обменный азот из межслоевого пространства монтмориллонита, тем самым обеспечивая пролонгированноепитание растений.

Ammonia capture from human urine to harvest liquid N-P compound fertilizer by a submerged hollow fiber membrane contactor: Performance and fertilizer analysis

In this study, we developed a submerged hollow fiber membrane contactor (HFMC) to recover ammonia from human urine to get compound N-P fertilizers. The ammonia capture performance, water vapor transmembrane performance, ion rejection performance and the liquid fertilizer components using 1–4 mol/L H3PO4 as the stripping solution was comprehensively investigated. Increasing H3PO4 concentration did not significantly affect the ammonia capture performance but the water vapor transfer and fertilizer components. The ammonia mass transfer coefficients were in a range of 1.95×10−6±4.77×10−8 to 2.28×10−6±6.71×10−8 m/s and the ammonia flux fluctuated between 17.80 and 20.80 g/m2·h. The water vapor flux increased with the increase of stripping solution concentration and the time elapsed. The N content (21.29–55.24 g/L) was in the range of the commercial products while the P2O5 content (99.41–281 g/L) was slightly higher, which can be used in the soils or plants with a high demand for phosphorus. The liquid fertilizers were all mixtures of (NH4)2HPO4 and NH4H2PO4, but the distribution ratio slightly changed with the different initial H3PO4 concentration. The economic assessment showed that harvesting liquid N-P fertilizer from human urine using HFMC can make a profit of $7.089/L.

Beetroot response to sodium chloride as a component of fertilizers

Sodium use combined with NPK fertilizers can potentially increase beetroot (Beta vulgaris L.) yield and quality. This hypothesis was studied in three field experiments with beetroot in Western Transbaikalia throughout the seasons 2012-2014. The effects of a combination of fertilizers and different Na amounts (10, 20, and 40 kg Na/ha) combined with the chloride on beetroot yield, storage root quality, and sugar accumulation were estimated. As a result, Na application increased beetroot yield by 13-22%, as compared to the mineral fertilizers along, and the highest Na dose contributed to the maximum beetroot yield. The rising of the root mean weight was detected. Also, crude protein and vitamin C were increased in beetroots, while crude fibre and nitrates were decreased. Along with increased sodium concentration, potassium amount in dry matter of roots and tops were declined. Both roots and tops were found to have more efficient P and N uptake.

Cohort Fertility Decline in Low Fertility Countries: Decomposition Using Parity Progression Ratios

BACKGROUND: The long-term decline in cohort fertility in highly developed countries has been widely documented. However, no systematic analysis has investigated which parity contributed most to the fertility decline to low and very low levels. Objective: We examine how the contribution of changing parity progression ratios varied across cohorts, countries, and broader regions in Europe, North America, Australia, and East Asia. We pay special attention to countries that reached very low completed cohort fertility, below 1.75 children per woman. Methods: Using population censuses and large-scale surveys for 32 low fertility countries, we decompose the change in completed cohort fertility among women born between 1940 and 1970. The decomposition method takes into account the sequential nature of childbearing as a chain of transitions from lower to higher parities. Results: Among women born between 1940 and 1955, the fertility decline was mostly driven by reductions in the progression ratios to third and higher-order births. By contrast, among women born between 1955 and 1970, changes in fertility showed distinct regional patterns: In Central and Eastern Europe they were fuelled by falling second-birth rates, whereas in the German-speaking countries, Southern Europe, and East Asia decreases in first-birth rates played the major role. Conclusions: Pathways to low and very low fertility show distinct geographical patterns, which reflect the diversity of the cultural, socioeconomic, and institutional settings of low fertility countries. Contribution: Our study highlights the importance of analysing parity-specific components of fertility in order to understand fertility change and variation. We demonstrate that similar low levels of completed cohort fertility can result from different combinations of parity-specific fertility rates.

Accumulation of microcapsules derived from coated fertilizer in paddy fields

Japanese agriculture uses large amounts of plastics. Fertilizer-containing plastic microcapsules with a diameter of 2–5 mm (“coated fertilizer”) are not recovered after use, and after diffusion of the fertilizer components these microcapsules are found in large quantities, not only on agricultural land but also along the coast of Japan. Here, we investigated the accumulation of microcapsules derived from coated fertilizer in 19 paddy fields. Microcapsules were detected in all of the paddy fields surveyed, at concentrations in the range of 6–369 mg/kg (mean 144 mg/kg)—much higher than the concentrations of microplastics in farmlands in other countries. There was no difference in mean microcapsule concentration between sampling sites with continuous rice cultivation and those with crop rotation, but that of a paddy field that had never received coated fertilizer was significantly lower. Examination of the spatial distribution of microcapsules in one paddy field showed that there was a hot spot with a high concentration near the drainage outlet. This was likely due to the strong influence of irrigation water flowing from the water inlet to the drainage outlet. The amount of microcapsules accumulated in Japanese paddy fields, as estimated from our results, and the amount applied to the fields, as estimated from the statistics, were almost equivalent. Therefore, most of the microcapsules that have already been applied to paddy fields may continue to accumulate. The impact of these high concentrations of microcapsules on the soil environment needs to be assessed.

Forest plantation productivity – soil interactions within Western Forest-Steppe of Ukraine: effects of pH and cations

Abstract Dark grey podzolized soils on the loess like loams, which are represented in the soil cover within fresh and humidity gradients in the Western Forest Steppe of Ukraine, are characterized by high forest vegetation potential, which ensure the formation of mostly pure and mixed larch and spruce stands with high level of the productivity. Despite the fact that both species are coniferous, their effect on the soil, in particular, on its acid-base indicators (actual and potential forms of acidity, sum of absorbed bases, degree of saturation of bases, content of mobile aluminium), which are important components of soil fertility, are specific. Due to the fact that there is a close interaction between forest plantations and soil properties, changing the participation of species in the stand, it is possible to adjust the actual soil fertility. The soils under both pure and mixed spruce and larch stands are characterized by a high level of potential acidity that reaches the high acidic values in the upper horizons. A similar reaction of soil solution under coniferous forests is caused by acid hydrolysis of aluminosilicates and accumulation of mobile Al in the rhizosphere zone. Simultaneously, the same acidic characteristics, including the presence of movable aluminium, are also found in soils under broadleaved plantations. In general, acid-exchange properties of soils (high potential acidity, unsaturation of bases and availability of movable aluminium) traditionally are considered as unfavourable for vegetation. However, our researches refute it and prove that within certain values, these indicators do not limit the productivity of pure and mixed spruce and larch stands.

Influence of the morphology of Co2O3 particles on the dissolution kinetics in electrolytes

Establishment of criteria for optimizing technological processes for dissolving transition metal oxides, separating metal compounds from depleted ores, removing oxide deposits from thermotechnical equipment, and methods for cleaning compounds are of practical significance. Cobalt and its compounds are important in the production of hard and heat-resistant alloys as organic synthesis catalysts, as a component of trace elements, fertilizers and drugs. Cobalt isotopes are used as radioactive labels in medicine, as fuel in spacecraft batteries. To solve the technological issues of replenishing the deficit of cobalt by processing cobalt raw materials and its regeneration from industrial waste, it is necessary to conduct targeted research, study the regularities of its behavior during chemical processes (leaching of ores and concentrates) and during electrochemical dissolution (obtaining cobaltcontaining intermediate products for further alloy smelting). One of the important factors affecting the kinetic parameters of the dissolution of cobalt oxides is the characterization of surface properties of the solid phase. The surface structure of powdery Co2O3 oxide was studied by X-ray phase analysis and electron microscopy. The chemical dissolution of the oxide in aqueous solutions of HCl was studied. The sizes and shapes of cobalt oxide particles, the nature of their surface distribution were determined, and kinetic curves of the chemical dissolution of Co2O3 were constructed. The independence of the oxide dissolution mechanism on the acid concentration was established. The kinetic parameters of the process were calculated (specific dissolution rate, reaction order with respect to hydrogen ion). A comparative analysis of the correspondence between the obtained experimental and available literature data was carried out. The obtained experimental and calculated results are of interest in studying the regularities of the dissolution of solid oxide phases of cobalt in various electrolyte compositions.The work was carried out with funding by D. Mendeleev Chemical Technical&nbsp;University of Russia, Project No. X-2020-011.

Antibiotic and antibiotic-resistant gene loads in swine slurries and their digestates: Implications for their use as fertilizers in agriculture

The spread of antibiotic resistance in bacteria is a matter of global concern, and the identification of possible sources of the associated genetic elements (antibiotic resistance genes -ARGs-, components of the horizontal gene transfer mechanism), is becoming an urgent need. While the transmission of ARGs in medical settings have been adequately characterized, ARG propagation in agroecosystems remains insufficiently studied. Particularly crucial is the determination of potential risks associated to the use of swine slurries and related products as component of organic fertilizers, an increasingly used farming practice. We determined ARGs and antibiotic loads analysed from swine slurries and digestates from eight farms from Catalonia (NE Spain), and compared the results with their microbiome composition. Both ARGs and antibiotic were conspicuous in farm organic wastes, and the levels of some antibiotics exceeded currently accepted minimum inhibitory concentrations. Particularly, the presence of high loads of fluoroquinolones was directly correlated to the prevalence of the related qnrS1 ARG in the slurry. We also found evidence that ARG loads were directly correlated to the prevalence of determined bacterial taxa (Actinobacteria, Proteobacteria, Spirochaeta), a parameter that could be potentially modulated by the processing of the raw slurry prior to their use as fertilizer.

Технологічні засади виробництва органо-мінеральних добрив із леонардиту

Goal. Improvement of the method of obtaining solid organo-mineral fertilizer with the use of leonardite. Methods. Laboratory-analytical, model, statistical. Results. Technological approaches to the processing of natural raw materials into organo-mineral fertilizers with the definite composition of nutrients are proposed. The expediency of enriching leonardite with a starting complex of nutrients, which enhances the fertilizer-stimulating effect and allows to obtain fertilizers with improved agro-chemical properties and increased physiological activity, has been scientifically substantiated. The optimal ratio in mixture of components of solid organo-mineral fertilizers is 1:1. Such mixture contains organic (leonardite with a moisture content of at least 40%) and mineral (a complex fertilizer N16P16K16) components. The mixture contain easily digestible form all 3 basic nutrients that significantly improve the quality of the final product without decreasing the functionality of mineral and organic components as a nutritional value for plants. The technology of preparation of solid organo-mineral fertilizers provides a separate stage of grinding organic and mineral components, during which they are stabilized. The next technological stage is the enrichment of leonardite in the appropriate ratio of the starting complex of nutrients with the replacement of water with mineral components and the process of saturation of leonardite with subsequent granulation and drying of the finished product. Conclusions. The proposed method of obtaining organo-mineral fertilizer is based on the use of available organic and mineral raw materials, which transform into organo-mineral form, balanced in the content of humic substances, macro- and micronutrients.

ВЫДЕЛЕНИЕ НОВЫХ ШТАММОВ БАКТЕРИЙ BACILLUS MEGATERIUM И ИЗУЧЕНИЕ ИХ БИОЛОГИЧЕСКИХ СВОЙСТВ

Bacillus megaterium is a gram - positive rod-shaped endospore-forming bacteria. They are used as an effective soil modifier, having the ability to disperse phosphorus. In turn, phosphorus plays an important role in several physiological and biochemical processes of plants, such as photosynthesis, the conversion of sugar to starch, and the transfer of genetic traits. Based on the current state of research in the development of biofertilizers, it can be argued that the biocomposition of Bacillus megaterium bacteria will lead to an increase in the availability of a number of macronutrients for plants – the main elements of nutrition. This article presents the results of screening studies of previously created collection of bacterial strains of Bacillus megaterium from the Museum of the Department of microbiology, virology, epizootology and VSE of Ulyanovsk SAU. The developed scheme of isolation and identification of Bacillus megaterium bacteria is given. The species identity of 6 strains of B. megaterium was confirmed. The results of the research are compared with the characteristic phenotypic properties of the studied species described in "Bergey's Manual of Systematic Bacteriology" (2015). 210 soil samples were taken to isolate new strains of microorganisms. Initial identification allowed us to isolate 58 strains of bacteria of the genus Bacillus, 16 were assigned to Bacillus megaterium. The percentage of contamination of soil samples of this type of bacteria was 7.6 %. As the result of research, the collection of bacterial strains of studied microorganisms was expanded and their taxonomic affiliation was determined. The resulting collection will be the object of research at the following stages of work on the development of biocomposition based on bacteria to increase the coefficient of absorption of mineral components of fertilizers.