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The impact of the active hostilities associated with Russia's large-scale armed invasion of the territory of Ukraine on soil degradation as a result of military actions has resulted in soil damage due to heavy military armored vehicles. Debris from destroyed military equipment, ammunition, and fuel remnants lead to multi-factor damage to the soil system, causing local and global pollution and losses of soil resources. In all the studied cases, mechanical, chemical, and physical soil degradation were observed. This was manifested in changes in granulometric fractions at explosion sites, burning areas, and locations with heavy-metal contamination. Equipment incineration has resulted in an increase in the sand fraction (2.0–0.05 mm) by 1.2–1.8 times and a decrease in the clay fraction (<0.002 mm) by 1.1–1.2 times. The soil contamination levels with regard to heavy metals significantly surpass health standards, with the highest pollution levels observed for Pb, Zn, and Cd. Across all affected areas, changes occurred in the microbiome structure (a 20.5-fold increase in the proportion of mycelial organisms), microbiological process activity was suppressed (a 1.2-fold decrease), microbial biomass (a 2.1-fold decrease) was reduced, and high soil toxicity (99.8%) was observed. Explosions and the pyrolysis of armored vehicles have a significant impact on soil mesobiota and plants. The results indicate the existence of complex interactions between various factors in the soil environment post-explosion, significantly affecting soil health. [ABSTRACT FROM AUTHOR]

Introduction: This paper presents comparative studies on the content and structure of organic matter (OM) and the activity of microbiological cellulose destruction in three types of Ukrainian soils intensively used in agricultural production. Methods: The highest content of humus in the arable layer (4.9%), OM (410 t ha-1), and total carbon (30.9 mg C g-1 soil) was determined in chernic phaeozems, which is 2.2-2.5 times higher than in albic retisols. The soil of natural ecosystems is characterised by a high content of microbial carbon (Cmic) in the carbon fraction of organic soil compounds. Results and discussion: In arable soils, the content and reserves of humus and soil organic matter (SOM) have decreased by an average of 1.5-2 times. The most considerable loss of humus reserves in the soil profile was identified in albic retisols (1.96-1.44 times) and the smallest in chernic phaeozems (1.27-1.81 times). During the long-term systematic application of mineral fertilisers, the Corg content decreased by 8-21% in chernic phaeozems, 12-33% in greyzemic phaeozems, and 6-38% in albic retisols. A significant difference of 2.1-8.0 times was determined regarding the number of aerobic cellulolytic microorganisms and 1.3-3.3 times in the potential cellulolytic activity of the studied soils. The high number of cellulose-destroying microorganisms is characteristic of chernic phaeozems with a high content of OM in the soil; the advantage over other types of studied soils was 1.4 times and 7.8 times for greyzemic phaeozems and albic retisols, respectively. Among the studied soil types, high values of CO2 emissions were identified in chernic phaeozems. Intensive agricultural practices in Ukrainian soils have significantly altered the content and composition of organic matter, leading to reduced humus and soil organic matter reserves. The study also underscores the importance of considering the abundance of cellulose-destroying microorganisms and their potential activity in assessing soil health and sustainability. [ABSTRACT FROM AUTHOR]

One of the main directions of agricultural production in Ukraine is the stabilisation and increase in the production of high-quality food grains, which will ensure the country's food security and increase the export potential. Increasing the yield of winter wheat (Triticum aestivum L.), the main grain crop of the country, is important in this regard. The purpose of the study was to investigate the influence of different intensity cultivation technologies on the productivity of winter wheat. The experiment was carried out in 2016-2020 and based on a stationary multifactorial experiment of the Department of Technology of Grain and Ear Crops of the National Scientific Centre Institute of Agriculture of the National Academy of Agrarian Sciences of Ukraine. Models of cultivation technologies were studied, which differed in the rates of applied mineral fertilisers, the insertion of pea straw residues, and the application of the plant protection system (PPS). The results showed a positive effect of the cultivation technologies with increasing intensity on the formation of winter wheat productivity. The amount of vegetative mass, the level of accumulation of the dry matter of plants, the density of productive stems, the length of the ear, the number of spikelets per ear, and the grain size of the ear increased. The factor 'fertilisation system' had the greatest influence (79.3%) on the formation of winter wheat grain yield. The highest grain yield was obtained by the highly intensive 1 (HI1) cultivation technology, which provided for the application of P80K100N240 fertilisers with the background of the straw residues of preceding crop and integrated PPS, which was 8.93 t ha-1 (excess to control was 4.71) with the best indicators of grains quality, protein content of 13.3-13.8%, and gluten content of 23.3-24.6%. On application of the studied technologies, winter wheat did not significantly accumulate copper, zinc, manganese, and iron. [ABSTRACT FROM AUTHOR]

Terrestrial ecosystems play a crucial role in the formation of soil resistome and the spread of antibiotic-resistant bacteria. Comprehensive studies of soil microbial communities, their structure, integrity, and level of antibiotic resistance (AR) in various terrestrial ecosystems were conducted. In total, 389 strains of dominant bacteria were isolated from the studied ecosystems, 57 of which were resistant to antibiotics, with levels of antibiotic resistance exceeding 70%. The soil microbiome of primeval forests was characterized by a low content of bacteria resistant to antibiotics; only two species, Bacillus cereus and Pantoea agglomerans, showed a high resistance to antibiotics. In the soil of agroecosystems of medicinal plants, among 106 strains of bacteria, a high level of resistance to antibiotics was found in 13 species. It was established that the number of antibiotic-resistant bacteria is highest in the soil of agroecosystems contaminated by enrofloxacin. Among 190 tested bacterial strains, 42 (22%) were characterized by a high level of antibiotic resistance. Therefore, the soil ecosystem is a key link in the formation and spread of antibiotic-resistant bacteria, which is a potential danger to humans. To reduce the risk of AR for humans, it is necessary to take appropriate measures to manage the soil microbiome and avoid soil contamination with antibiotics. [ABSTRACT FROM AUTHOR]

An increase in the pesticide load in agro-cenoses leads to a decrease in the number of the main ecological and trophic groups of microorganisms, which causes a disruption of connections in agro-ecosystems and soil biological activity. For example, more than 95% of applied pesticides have a greater impact on soil microorganisms than on their target objects, as they are sprayed proportionally all over the field, regardless of the affected areas. In this case, fire treatment has the main benefit of a more targeted treatment, which is more focused on its main object of impact. But, as you know, fire can also cause significant damage to both soil and microorganisms living there. Soil microbiota is very sensitive to environmental changes, but it is completely killed only at soil temperatures above +120°C, so treatment with a fire cultivator that can work at both +100°C and +70°C has a high chance of becoming the safest way to control weeds. Despite the known negative effect of fires and flames on soils, to fully assess the impact of this method on soil and its fertility, it is necessary to investigate the impact of this treatment primarily on changes in the microbiological characteristics of the surface soil layer. The treatment was carried out using two modes of the fire cultivator (+70°C and +100°C). Microbiological analyzes of the soil were carried out according to generally accepted methods. The content of total biomass of microorganisms in the soil was determined by the rehydration method. Thus, to study the impact of fire cultivation on the direction of processes in the soil and the main ecological and trophic groups of microorganisms, we determined the content of total biomass of microorganisms, coefficients of mineralization-immobilization and oligotrophicity, cellulolytic activity, the number of bacteria, micromycetes, etc. Our analysis of the total microbial biomass of the selected soil samples allows us to assert the safety of the applied fire method of weed control. In the study of soil fouling lumps (Ashby's medium), 100% presence of bacteria of the genus Azotobacter was noted in all variants with temperature treatment. The analysis of soil samples on Ashby's medium showed that oligotrophs do not significantly change under fire treatment at 70°C, but some negative impact on the vital activity of these microorganisms is still observed under 100°C treatment. The obtained ecological coefficients of the direction of microbiological processes indicate the decreasing intensity of decomposition of soil organic matter, in particular humus compounds and reducing soil oligotrophicity indicates an increase in the content of nutrients in the soil. For the most environmental benefits, we recommend to use a milder fire treatment of 70°C, wich allows not only to control the weeds, but also stimulates and directs microbiological processes in a positive directio. [ABSTRACT FROM AUTHOR]

There are a number of questions that have remained relevant for a long time when using inoculants based on nodule bacteria. It has been shown that exopolysaccharides (EPS) producing bacterial cells play one of the key roles during interaction and during signal transmission in legume-rhizobial symbiosis, namely, bacterial survival, virulence of rhizobia, shelf life on inoculated seeds and in soil, and efficiency created legume-rhizobial system. In particular, it was found that new strains of soybean nodule bacteria Bradyrhizobium japonicum LG 2 and LG 5 synthesize EPS at 3.2 and 2.8 g/l, with an optical density above 0.8 rel. units, the viscosity of the culture liquid - within 270-302 mPa • s. The high level of synthesis and the chemical composition of EPS of the studied strains ensured the preservation of the viability of bacterial cells on the surface of seeds and on a solid medium. Inoculation of soybean seeds with a culture liquid containing EPS of strains LG 2 and LG 5 ensured the formation of an effective legume-rhizobial system, which is confirmed by the formation of 18-21 nodules / plant of soybeans with a nitrogenase activity of at least 2.9 µmol C2H4 / plant per hour. A graph model has been developed, which proves the direct dependence of the effect of EPS on the number of nodules formed on the roots, the level of nitrogenase activity of the legume-rhizobial system and their indirect effect on the yield and protein content in soybean grain. Prospects isolated by strains LG 2 and LG 5 of B. japonicum for biotechnological production of liquid and gel biopreparations. [ABSTRACT FROM AUTHOR]

The article presents original results of research. The dynamics of the balance and NPK use efficiency of the typical Ukrainian farm for monoculture cultivation during 2016‒2018 has been calculated. Laboratory analysis of soil (pH value, humus content, N, P2O5 and K2O) and grain (N and P2O5 content) was conducted in 2019. The negative dynamics of basic nutrient balance in the soil was revealed for 2016–2018 (nitrogen deficiency ranged from ‒30,6 to ‒130,9 kg/ha/year, phosphorus ‒ from ‒25,8 to ‒62,4 kg/ha/year, potassium ‒ from ‒34,3 to ‒244,5 kg/ha/year) and intensive pressures on the soil (NUE = 77,0‒260,3%, PUE = 171,3‒1902,3% and KUE = 115,8‒1429,8%). Soil pH was found on average 5,6 (category: close to neutral), the nitrogen content averaged 99 mg/kg (very low level), Р2О5 content ‒ 208 mg/kg (high level) and К2О ‒ 119 mg/kg (medium level) on the farmland areas. The ratio between nitrogen, phosphorus and potassium content in the soil of the studied land areas on average reaches 1:0,9:1,2 while the scientifically sound norm is 1:0,9:0,8. The average humus content is 1,93% (low level). The calculated indicators of nitrogen and NUE balance only in 2017 met the recommended standards of the UN Economic Commission for Europe. The PUE and KUE values in 2016 exceeded the average rate of phosphorus and potassium removal from the soil – 22 and 12 times, respectively. Changes of acidity over the last three years indicate the acidification of the soil environment, which is quite natural: only nitrogenous mineral fertilizers are applied to the soil, which is physiologically acidic, soil liming is not carried out, the green manure crops are not sown, organic fertilizers are not applied, and in crop rotation was a monoculture. The widespread practice of plowing crop residues into the soil without applying phosphorus and potassium fertilizers for three years does not meet the crop requirements for phosphorus and potassium and creates high one-way pressure on the soil. Consequently, relatively high sunflower and maize yields are generated from the existing high and medium content of these elements in the soil. The tendency of decreasing humus content in soil has been noticed. [ABSTRACT FROM AUTHOR]

Soil microbial communities play an important role in ecosystems functioning and are on the field scale essential for plant nutrition and health. On a larger scale, they contribute to global element cycling. Furthermore, they are involved in the turnover processes of organic matter, the breakdown of xenobiotics and the formation of soil aggregates. An ecological state of soils depends on the structure and activity of soil microorganisms. The results of soil monitoring in various ecosystems in different climatic zones of Ukraine showed a clear trend for the correlation between the agroecological conditions and activity of microbiocenosis. The most significant influence of agricultural activity on the soil microbiota can be observed on the poorly soddy-podzolic and gray forest soils, where the crop cultivation without fertilization resulted in a decrease in the total count of microorganisms by 2.2-4.5 times. Application of agricultural measures aimed at achieving maximum productivity, specifically the combination of mineral, organic and biological fertilizers, contributes to an average 1.3-4.1 times increase in the total count of microorganisms in the soil, compared with non-fertilized variants. Soils with low content of organic matter and acidic medium, soddy-podzolic and gray forest soils were characterized by a high number of micromycetes, 136-185×103 CFU·g-1 soil, and a relatively low number of eutrophic and nitrogen-fixing microorganisms. The soil of natural ecosystems is characterized by a high total count of the microorganisms with a balanced structure of various ecological-trophic groups and balanced processes of mineralization-immobilization, organic matter decomposition, and humus accumulation. [ABSTRACT FROM AUTHOR]

Terrestrial ecosystems may provide an ideal setting for the acquisition and dissemination of antibiotic resistance, because they are frequently impacted by anthropogenic activities. The soil microbiome plays an important role in development and spread of antibiotic resistance in humans. The aim of our study was to detect the antibiotic resistance soil bacteria in different ecosystems: natural ecosystems, agroecosystems and urboecosystems. Were isolated 468 dominanting bacteria, among them 79 antibiotic resistant bacteria. All isolates were multi-drug resistant, of which greater than 74,5% were resistant to 9 antibiotics. A study of soil samples from the primeval forests showed that the microbial community characterized by a low content of antibiotic-resistant microorganisms. Among 78 isolated bacteria only two of them Bacillus cereus, and Pantoea agglomerans demonstrated high level of resistance to antibiotics. A total 106 strains were isolated from the soil of medicinal plants, 13 of them were antibiotic-resistant. The greatest numbers of antibiotic-resistant bacteria have been isolated from soil of urboecosystems and agroecosystems contaminated by enrofloxacin. Among the 284 tested bacteria 64 were antibiotic resistant. Multi-resistance were such pathogenic and conditionally pathogenic bacteria as: Enterococcus faecium, Acinetobacter baumannii, Pseudomonas aeruginosa, Escherichia coli, Bacillus licheniformis, Serratia fonticola, Hafnia alvei, Bacillus cereus, Bacillus megaterium and Clostridium difficile. [ABSTRACT FROM AUTHOR]

The content and stocks of carbon and the activity of microbiological destruction of organic matter in three types of chernozem soils in Ukraine have been investigated. An imbalance was found in the accumulation of the main components of the soil organic matter, as well as between mineralization processes, humus accumulation and degradation of cellulose in arable soils and their natural analogs. In the soil of natural ecosystems, the processes of mineralization -immobilization, destruction of organic matter and humus accumulation are balanced, which is confirmed by a high carbon pool (Ctot) and a fraction of Сmic in Ctot. In the soil of natural ecosystems processes of mineralization-immobilization, destruction of organ resources and humus-accumulating are balanced, which is confirmed by high-quality carbon pool and partial Сmic in Ctot. In agroecosystem is going destabilization of organic matter in the soil, which leads to a decrease of humus content in 1.1-1.5 times, stocks of organic matter - in 1.3-1.8 times. In arable soils, part of Соrg in the total soil carbon pool is 80-82% and 92-94% in the soil of the natural ecosystem. The losses of Соrg from chernozem soils in agroecosystem are 19-29% and this is due to a significant reduction in the content of Сmіc (63-71%). The application of different fertilizers causes destabilization of the soil microbial community, reduces microbial productivity and activates mineralization processes of organic matter, which leads to loss of Соrg and a decrease in the total carbon pool (Ctot) in the soil by 6-18%. The soil of natural ecosystems is characterized by a high content of Сmіc in the Соrg (3.14-3.70%), which indicates a high microbial productivity and fixation of organic substances in biomass of microorganisms. In the arable soils, was the low content of Сmіc in the organic matter of the soil (1.19-1.52%) which indicates the predominance of mineralization processes over the processes of humification. The application of exogenous mineral substances in the soil activates the processes of mineralization (Kmіn increases by 7-18%) and provides a high degree of using by microorganisms of soil organic matter (Kped increases by 6-9%). Organic fertilizers contribute to the formation of a maximum microbial pool, optimizing the structure of soil microbial community, decrease the intensity of mineralization processes (Kmіn) by 15-29% and the decomposition of soil organic matter by 6 to 37%. A significant difference in the parameters of the potential cellulolytic activity of the soil in the natural ecosystems and agroecosystems had been established. At the same time, the soil of natural ecosystems is characterized by a slight fluctuation of the emission CO2 (3.3-4.4 mg CO2 / kg of soils per day). [ABSTRACT FROM AUTHOR]