Humus Content Research Articles

Combining citrus waste-derived function microbes with biochar promotes humus formation by enhancing lignocellulose degradation in citrus waste compost.

The low degradation rate of lignocellulose limits the humification process of citrus organic waste composting. This study explored the roles of general microbial inoculation (GM), citrus waste-derived function microbial inoculation (CM), and CM combined with biochar (CMB) in citrus waste compost. Results showed microbial inoculations all promoted lignocellulose degradation and humus formation, but the roles of CM and CMB were better than GM, especially CMB. Compared to the control, CMB raised the temperature and duration of thermophilic phase by 2.8 °C and 4 days, and improved lignin degradation rate and humus content by 21.5% and 7.6%. Furthermore, CMB promoted bacterial community succession and cooperation, and decreased network complexity. Moreover, CMB strengthened the correlation between mainly bacterial communities and polysaccharides, reducing sugars as well as carbohydrates metabolic, enhancing the contribution of bacteria such as Bacillus, Flavobacterium and Staphylococcus to humus and its precursors. It concludes that the naturally derived microbes in compost had better effects on promoting humus synthesis than exogenous microbes, which provides a new route for rapid humification of high-lignin organic waste in composting.

Agroecological estimation of the effect of crop rotation and mineral fertilizers on productivity and quality of spring barley grain in the Central Blackearth region of Russia

The purpose of the current study was to determine the effect of crop rotations and doses of mineral fertilizers on productivity, grain quality of spring barley and fertility of typical chernozem in the Central Сhernozem Region (CBR). The study was conducted in a multifactorial trial located on the watershed plateau of the research and production department No. 2 of the Federal Agricultural Kursk Research Center in 2018 and 2022. The soil of the experimental plot was typical medium-loamy chernozem, with 5.9 % of humus. There have been studied such factors as grain-fallow-row and grain-grass-row crop rotations; with fertilizer doses and no fertilizers, N30Р30К30, N60Р60К60. The highest biological productivity of spring barley up to 5.99 t/ha was identified in the grain-fallow-row crop rotation with the dose of N60Р60К60. However, the presence of perennial leguminous grasses in the grain-grass-row crop rotation contributed to a smaller decrease in humus, the maximum loss of which in it was 0.14 %, which was 0.02 % lower than in the grain-fallow-row crop rotation. The trends of agroecological effect of crop rotations and mineral fertilizers on the indicators of spring barley grain production were estimated with a digital method, namely the Harrington desirability function. There has been established an “acceptable, satisfactory” effect of crop rotations and mineral fertilizers on the studied indicators (di = 0.50), but in relation to individual indicators of grain production, the level of effect of crop rotations varies significantly from di = 0.12 “completely unacceptable” to di = 0.83 “most acceptable”. The ecological properties of crop rotation are manifested in the estimation of its effect on the humus content in the soil: “acceptable, satisfactory” (di = 0.38–0.52). The comprehensive estimation of the effect of mineral fertilizers for most indicators has increased proportionally to their dose, reaching di = 0.49–0.65, which indicates their “acceptable, satisfactory” effect.

Sustainable Nitrogen Management in Rice Farming: Spatial Patterns of Nitrogen Availability and Implications for Community-Level Practices

Sustainable nitrogen management is crucial for long-term food security and environmental protection in rice farming systems. However, the spatial patterns of nitrogen availability at the community level remain poorly understood, hindering the development of effective sustainable management strategies. This study introduces a novel application of spatial autoregressive analysis to investigate available nitrogen distribution in paddy soils across a rice farming community in Kyoto, Japan. Soil samples from 61 plots, including organically farmed ones, were analyzed for available nitrogen and various physicochemical properties. Contrary to the hypothesis of high variability between adjacent plots, significant positive spatial autocorrelation in available nitrogen was observed, revealing previously unrecognized community-level patterns. The spatial Durbin model outperformed traditional regression approaches and revealed complex spatial interactions in soil properties. Water-soluble organic carbon and humus content showed strong but opposing effects, with a positive direct impact but negative spatial interaction, suggesting topography-driven accumulation processes. Water-soluble nitrogen exhibited reverse patterns with negative direct effects but positive spatial interaction, indicating potential nutrient transport through water movement. These findings highlight the importance of considering both direct and indirect spatial effects in understanding soil fertility patterns, challenging the conventional plot-by-plot management approach. This methodological advancement provides new perspectives for more effective, community-scale soil management strategies in rice farming systems. Moreover, it demonstrates an innovative approach to maximizing the value of outsourced soil analysis data, providing a model for more comprehensive utilization of such data in agricultural research. By enabling more targeted and efficient nitrogen management practices that consider both plot-level processes and landscape-scale interactions, this study potentially contributes to the development of more sustainable and resilient rice production systems.

Humic Substances from Waste-Based Fertilizers for Improved Soil Fertility

This research explores how different organic waste transformation methods influence the production of humic substances (HSs) and their impact on soil quality. Using olive and orange wastes as substrates, the study compares vermicomposting, composting, and anaerobic digestion processes to determine which method produces the most humic-substance-rich products. The characterization of HSs in each product included analyses of total organic carbon (TOC), humic and fulvic acid content, humification rate, humification degree, and E4/E6 ratio, with HSs extracted using potassium hydroxide (KOH) and analyzed via Diffuse Reflectance Infrared Fourier-Transform (DRIFT) spectroscopy to assess structural complexity. The results revealed that the chemical composition of the input materials significantly influenced the transformation dynamics, with orange by-products exhibiting a higher humification rate and degree. Vermicomposting emerged as the most efficient process, producing fertilizers with superior humic content, greater microbial biodiversity, and enhanced cation exchange capacity, thus markedly improving soil quality. Composting also contributed to the stabilization of organic matter, albeit less effectively than vermicomposting. Anaerobic digestion, by contrast, resulted in products with lower levels of HSs and reduced nutrient content. Aerobic processes, particularly vermicomposting, demonstrated the most rapid and effective transformation, producing structurally complex, stable humus-like substances with pronounced benefits for soil health. These findings underscore vermicomposting as the most sustainable and efficacious approach for generating HS-rich organic fertilizers, presenting a powerful alternative to synthetic fertilizers. Furthermore, this study highlights the potential of organic waste valorization to mitigate environmental pollution and foster circular economy practices in sustainable agriculture.

Efficient resource recovery from food waste digestate via hydrothermal treatment and its application as organic fertilizer

With the continuous recognition of green, organic and non-polluting products, organic fertilizers play an increasingly vital role in agricultural production. Among them, hydrochar-based organic fertilizer has attracted widespread attention recently. The present study evaluated the potential of digestate from anaerobic digestion of food waste for the preparation of hydrochar-based organic fertilizer by straw-based, FeCl3-catalyzed hydrothermal carbonization (HTC). Under the optimal conditions, a hydrochar-based organic fertilizer with > 25 wt% humus content and limited pollution risk was successfully prepared. The pot experiment demonstrated the feasibility of improving the physicochemical properties of red soil and promoting crop growth after adding hydrochar in place of commercial fertilizer. In addition, the function of zeolite on nutrient recovery in hydrothermal liquid (HTL) was analyzed, and preparing the slow-release organic fertilizer by mixing the nutrient-rich zeolite with hydrochar in a mass ratio of 1:4 was proposed. This work has significant implications for achieving the efficient resource recovery of digestate.

The synergistic interaction of fungi with different structural characteristics improves the leaching of lithium from lepidolite

The aim of this study was to explore the improvement of lithium leaching from lepidolite by microbial co-culture, focusing on the synergistic effect of different structural fungi in improving the leaching performance of biological systems. The results showed that in the single leaching experiment, the multicellular fungi and the unicellular yeast showed weak effects. Multicellular fungus is limited by insufficient EPS secretion, while unicellular yeast is non-mycelial organisms with weak acid production capacity and limited effect on minerals. However, in the combined leaching experiment, the interspecific collaboration promoted the synthetic and metabolic activity of the two strains, resulting in changes in the type and content of organic acids, polysaccharides, proteins and humus. The content of citric acid reached the highest value of 16.98g·L-1 at about 22 d, and the EPS secreted by unicellular yeast promoted the mycelium adhesion and mineral wrapping of multicellular fungi. The combined action of the two enhanced the effects of acidification, complexation and mycelium destruction, and improved the leaching effect. This study revealed the synergistic metabolic mechanism of lepidolite leaching by fungi with different structures, verified the effectiveness of microbial co-culture to improve the leaching rate, and provided a basis for industrial application. In addition, the use of co-culture technology has a positive impact on commercial production and environmental protection.

Bioecology of Cinnamomum culitlawan (L.) J.Presl (1825) Endemic Species on Halmahera Island

Cinnamomum culitlawan (L.) J. Presl (1825) is an endemic plant belonging to the Lauraceae family. The plant growth is found in Indonesia, especially in Maluku and Papua. This study aims to: (1) understand the taxonomy of C. culitlawan; (2) find out its habitat, environmental adaptation, and ecological role; and (3) find out its utilization and ethnobotany. This study was conducted by combining the literature review method with the survey method. Efforts to understand the taxonomy, utilization, and ethnobotany of C. culitlawan through a literature review. Each plant specimen found in the documentation was observed for its distribution, habitat, adaptation, and interaction. Taxonomic and ethnobotanical studies were conducted by literature review. The results of the study showed that C. culitlawan has 12 synonyms, namely Benzoin gracile (Nees) Kuntze; C. culiban Raf.; C. culitlawan var. rubrum (Blume) Meisn.; C. rubrum Blume; Daphnidium gracile Nees; Laurus culiban L.; Persea culilawan (L.) Bisch.; Laurus culilawan Nees; Laurus culawang Nees; Laurus culitlaban Roxb.; Laurus culitlawan L.; Laurus glauca Nees; Laurus gracilis Meisn.; and Persea culilawan (L.) Bisch. Some researchers wrote it with the species name Cinnamomum culilawan Blume, a synonym that has not been verified in WFO. Generally lives in low to medium plains, in areas with high rainfall. C. culitlawan has adapted to high humidity and grows in soil with high humus content. C. culitlawan has complex interactions with other species, including pollinating insects and soil organisms. C. culitlawan has important value in ethnobotany aspects, including traditional medicine, culinary, and cultural rituals.

Effects of soil acidification on humus, electric charge, and bacterial community diversity.

Soil acidification due to the long-term application of nitrogenous fertilizers and the consequent impact on crop growth have been frequently reported. The effects of acidification on soil humus, charge, and microbial communities need to be studied. In this experiment, fertilizer drenching was used to simulate the effects of multiple years of fertilizer application on the black soil. The results showed that 25years of soil acidification treatment resulted in a decrease of 8.97% in the content of stable humus and led to a decrease of 58% and 51.18% in the humic acid (HA) content and degree of humification (PQ) value in stable humus, respectively. In addition, soil acidification leads to a significant decrease in total negative charge (CEC8.2) and variable negative charge (CECv), with both decreasing by 63.28% and 88.67%, respectively, at 25years. Acidification treatments affected both soil microbial community abundance and diversity, with a significant decrease in Acidobacteriota and Gemmatimonadota abundance and an increase in Bacteroidia abundance and Acidobacteriota abundance at 25years.

Manifestation of selection traits and properties of forage productivity in groups of alfalfa varieties with different resistance to viral and phytoplasma infections

The research was conducted in 2019–2023 in Belgorod region with the purpose of breeding evaluation of alfalfa cultivars with different resistance to «witches’ broom alfalfa» (WBA). Fifty-two selection samples belonging to species Medicago sativa L., M. varia Mart., M. falcata L. The soil is typical chernozem, humus content (according to Tyurin) 4.7…5.0 %, The year of sowing – 2019. Predecessor – pure fallow. Plots – two-row long 3.5 m, row spacing width – 0.3 m. Repetition – five times. Standard – variety Belgorodskaya 86, sown through 5 numbers. Seeding rate of 100 germinated seeds per 1 linear meter. It was found that the group of varietal samples (n = 10) with low resistance to WBA (variation of prevalence 24.3–34.9 %) is characterized by a greater accumulation of protein (by 44.6 g/kg, t = 8.0, p 0.05), higher foliage (by 4.8 %, t = 3.7, p 0.05) and height (by 25.3 cm, t = 6.2, p 0.05), compared to the group of varieties resistant to WBA (n = 12) (prevalence variation 4.6… 9.1 %). Varieties with high resistance to WBA, belong to yellow and yellow-hybrid alfalfa varieties: Pavlovskaya 7, PO-172, Marusinskaya 425, PO-173, Sarga, PO-174, Victoria, 20–89 H, 193–95d, PO-175, SGPR-8, Vela×Sarga. Varieties with low resistance to VML belong to blue alfalfa and partially – blue-hybrid varieties: Krasnoyaruzhskaya 2, SI-139, SI-138, Plateau, Verko, Luzelle, Salsa, Kreno, Galaxi, Planet.

Ecological Capacity and Bioenergy Potential of Agrocenoses as a Way of Sustainable Agriculture

Background: Calculation of bioenergy potential and ecological capacity are promising methods for assessing the state of an agro-landscape, allowing us to promptly respond to changes in its sustainability. The article presents the results of soil research and calculation of bioenergy potential of the farm territory in the zone of dry steppe on chestnut soils. Methods: Assessment of anthropogenic load on agricultural landscape is based on ecological standards and point system of relative fertility. The determination of the ecological capacity by BEPT of an agrocenosis occupied by winter wheat and sunflower was carried out according to the method of V.M. Volodin, R.F. Eremina, N.F. Mikhailova. Determination of erosion and geomorphological characteristics of the research object was carried out using geoinformation technologies. The basis for creation of digital elevation model (DEM) is the data of radar survey of the Earth surface (SRTM4). Result: Soils of the research object have low and average humus content. Nitrogen level in the soil varies from very low to good; nitrogen availability in the fields is average. Provision with mobile phosphorus is average. Soil potassium content is mostly high. As a result of calculations, it was found that in the conditions of the dry steppe zone, the bioenergy potential of the agrolandscape area occupied by winter wheat is 2735.72 GJ/ha, sunflower-2647.4 GJ/ha. At the same time, the ecological capacity of the field occupied by winter wheat is 2764.6 GJ/ha and sunflower-2676.8 GJ/h.

Влияние насаждений Quercus robur L. и Juglans rupestris Engelm. на свойства степных почв

The aim of the study has been to determine the condition of Quercus robur L. and Juglans rupestris Engelm. and their influence on the properties of segregated chernozems. The study was conducted in 2020–2021 in the steppe Crimea. The control has been a perennial grass fallow. To characterize the general condition of the trees, a 4-point scale for assessing the condition of the introduced species has been used. Standard methods have been used for soil analysis. A better preservation and a greater number of 50-year old plants in excellent and good condition have been established for Q. robur (67 и 56 %, respectively) compared to J. rupestris (48 и 42 %, respectively) in these environmental conditions, which is explained by the greater adaptive capabilities of oak as an indegenous species. Both tree crops have influenced soil properties. In their phytocenoses, a litter has been formed, more significant under J. rupestris. The dark humus horizon has also turned out to be thicker under the J. rupestris plantation (80 cm) than under the Q. robur plantation and the fallow (72 and 70 cm, respectively). Under Q. robur the soil density has been lower than under J. rupestris by 0.02–0.18 g/cm3. Under the woody plants, the soil structure has improved: the number of lumpy aggregates has decreased, and the number of agronomically valuable and granular particles has increased. The maximum coefficient of structure has been in the soil under the oaks (4.4–6.6), which exceeded the control by 2.5–4.9 times. Under the woody plants, carbonates have been significantly washed out of the soil profile, especially under J. rupestris. The pHH2O value of the alkaline soil under the woody plants has decreased by 0.2–0.4 and has been closely related to carbonate content (r = 0.83–0.91). The humus content under both species has been significantly higher than under the fallow – by 0.30–0.86 %. Afforestation has resulted in the accumulation of total forms of nutrients, to a greater extent under J. rupestris, and the C:N ratio has decreased. Tree species have stored more labile forms of nutrients in the soil. Soil desalination has been noted in the tree cenoses. Thus, J. rupestris and Q. robur are ecologically stable in the conditions of the central steppe of Crimea and can be used to increase forest cover in steppe areas. This will help improve soil fertility.

No-till, crop residue management and winter wheat-based crop rotation strategies under rainfed environment

Rainfed agriculture is primarily limited by unstable low precipitation, poor soil fertility and monocropping, which are the main factors leading to decreased crop production. This long-term research was conducted under a rainfed agroecosystem from 2019 to 2023 on the sierozem soil of the Karshi steppe, Uzbekistan. Along with winter wheat (WW) which was the main crop covering 50% of each proposed cropping pattern, chickpea (CH), safflower (SA), flax (FL), barley (BA) and canola (CA) were evaluated to find the most suitable rotation systems under no-till (NT) i.e. NT1: WW–CH–WW–FL, NT2: CH–WW–SA–WW, NT3: WW–SA–WW–BA and NT4: SA–WW–CA–WW compared against continuous WW produced with conventional tillage (CT). Results showed that the integrated effect of NT x crop diversification x residue retention positively affected crop productivity; however, their impact were significantly higher under the NT2 treatment, but not with continuous WW under CT. The highest grain yield of WW in the 2020-2021 growing season was recorded under NT2 and NT4 treatments with values of 1.47 and 1.30 Mg ha-1, while the lowest index (1.02 Mg ha-1) was found at the CT treatment. The grain yield in the NT treatments increased with the improvement of soil chemical and physical parameters, i.e. NPK and humus content. When comparing NT2 to CT treatment at the project end, the total N, P, and K values at the 0–20 cm soil profile were 27.9%, 13.9%, and 33.9% higher, respectively. This study concluded that implementation of NT along with strategic selection of legumes incorporated into the cropping system and residue management can be prioritized as rehabilitation measures in rainfed croplands.

Assessment of spatial variability of agrochemical properties of agro-gray soil when planning a feld experiment with mineral fertilizers

The purpose of the work is to investigate the statistical parameters and patterns of variability of agrochemical indicators of agro–gray soil, elements of the structure of the spring wheat crop within the plots of the experimental field. Experimental data were obtained on the basis of observations conducted on agricultural landscapes Sukhobuzimskoye land areas in the Krasnoyarsk forest-steppe of the Krasnoyarsk geomorphological district, located borders the Chulym-Yenisei denudation plateau in the southwestern outskirts of Central Siberia. The results of the intra-field heterogeneity of the agrochemical properties of the agro-gray soil and the elements of the structure of the spring wheat crop on the site intended for field experiment are presented. The key statistical and geostatistical values of the intrafield heterogeneity are determined. The statistics of agrochemical indicators and the results of crop data from the plots intended for the placement of repetitions are analyzed. The materials of the agrochemical survey of the agro-gray soil revealed a low humus content. The level of spatial variation of the indicator corresponded to the average. The scope of variation is represented by values covering only one gradation of the evaluation scale. The entire studied area was characterized by a slightly acidic reaction of the medium according to the average pH values. Its variation in the 0-20 cm soil layer indicated uniformity of distribution in space. The level of variability of agrochemical indicators decreased in the following series: yield (40 %) > humus (19 %) > P2O5 (13 %) > K2O (10 %) > pH2O (4 %). According to the generalization of geostatistical information, the analyzed site is classified as unaligned in terms of soil fertility. In general, the soil fertility of the studied area had a significant variation, which determined the choice of elements of the field experience methodology. When laying out field experience, it is necessary to choose the appropriate elements of the methodology: a randomized method of placing repetitions, rectangular or elongated forms of plots.

Involving unused land in the economic turnover of the agricultural sector of a region: institutional regulation and economic feasibility

The article shows the necessity of institutional regulation of the process of involving unused agricultural land into the economic turnover of the agrarian sphere of a region. It presents quantitative and qualitative characteristics of previously withdrawn agricultural lands, their territorial distribution by soil and climatic microzones and administrative districts of a region, unused period duration, residual fertility level (in terms of humus content), and land plots degradation degree. A calculation-analytical complex such as an algorithm representing a four-stage mechanism of analysis, preparation and decision-making on the choice of the land plots restoration method and their further use option has been developed and proposed for use. It is recommended to use three options for land plots restoration: direct return to economic turnover in case of a short period of non-use; carrying out cultural and technical measures with subsequent implementation into the turnover; transfer to another category of use in case of a high degree of degradation and low fertility level. The developed algorithm of unused agricultural land involvement is aimed at preserving the land potential of a region, strengthening the rational land use system. The presented stages provide not only theoretical and methodological, but also practical significance. Application scope is scientific organizations, agroindustrial complex management bodies at the municipal and regional levels, and agricultural producers.

Changes in DOM and alum doses for two rivers of contrasting catchments after intense wildfires

ABSTRACT The dynamics of dissolved organic matter (DOM) in two river waters were investigated after their catchments had been severely burnt in the 2019/2020 Australian wildfires. Shortly after these wildfires, dissolved organic carbon (DOC) concentrations were recorded at high levels (∼19 and 30 mg/L) and these became much lower (up to ∼80% less) in the following winter when river flows had increased. Satellite imagery-based data indicated up to 95% of catchment areas burnt and up to ∼50% subsequent vegetation recoveries after 2 years. Shifts in burn index values for the burnt areas coincided with DOC concentration variations. The specific colour of waters increased up to 40% as daily river flows increased, indicating higher input of humic content from the burnt catchments. Chlorophyll a was detected at the highest levels in the waters soon after the fires when river flows were lowest. Enhanced alum doses were predicted using two feed-forward models; one based on DOC and turbidity data and the other based on UV@254 nm, colour, and turbidity. The doses predicted using the two models showed high correlations (r > 0.9) and were highest for waters directly after the fires. These models were developed for diverse source waters including those impacted by extreme climate events.

Towards a national model of humus (carbon) budget management in soils of agroecosystems in the Russian Federation

The prospect of adapting two methods for monitoring the fertility of agricultural soils (humus balance, HB) under spring and winter wheat crops (hereinafter referred to as grain crops) developed in the Russian Federation (RF) for the purposes of climate projects has been studied. It was revealed that the RosNIIzemproekt method (1998) underestimates the HB average value to -7.7 c/ha for RF. The RosNIIzemproekt method (1998) has logical errors in the calculation model and is not recommended for use. The TsINAO method (2000) has a more logical calculation model. According to this method, the average value of HB in soils for RF is generally positive and amounts to 3.3 c/ha (0.71 tCO2-eq/ha carbon units). This value constitutes ≈0.3% of average humus reserves in arable soils of the RF (108 tС/ha). The annual value of change in humus content under spring and winter wheat is incommensurably less than the total humus reserves in the soil. Statistically reliable assessment of changes in humus content requires a huge number of soil samples. This makes the verification procedure economically inexpedient. Another option is proposed to increase the time of humus accumulation. It is considered (IPCC, 2003) that a 20-year accumulation period is sufficient, which corresponds to the duration of soil climate projects. A coefficient (0.216) has been proposed for converting humus reserves (c/ha) to the value of a carbon unit (tCO2-eq/ha). The total sequestration of carbon by soils under grain crops in 2022 was about 11 million 914 thousand tCO2-eq. HB accounting significantly compensates for calculated emissions from agricultural production and reduces them by almost 10% (from 116 to 105 million tons CO2-eq in 2022). For both models of fertility monitoring, an assessment was made of the quality of the regression dependence of HB on the total biomass of photosynthesis (TBP) in soils under grain crops. It is shown that according to Fisher's t-test at a 5% significance level, the studied relationship is significant and characterized by the squares of the correlation coefficient (R2) equal to 0.554 and 0.998. In accordance with the Chaddock scale, the closeness of the correlative relationship between HB and TPB for winter wheat is assessed as high, and for spring wheat as very high.

Enhancing nitrogen transformation and humification in cow manure composting through psychrophilic and thermophilic nitrifying bacterial consortium inoculation

Excessive nitrogen release during composting poses significant challenges to both the environment and compost quality. Biological enhancement of humification and nitrogen conservation is an environmentally friendly and cost-effective approach to composting. The aim of this study was to develop a psychrophilic and thermophilic nitrifying bacterial consortium (CNB) and investigate its role in nitrogen transformation and humification during cow manure composting. Analysis revealed that CNB inoculation promoted microbial proliferation and metabolism, significantly increased the number of nitrifying bacteria (p < 0.05), and elevated the activity of nitrite oxidoreductase and nxrA gene abundance. Compared to the control, CNB inoculation promoted the formation of NO3–-N (77.87–82.35 %), while reducing NH3 (48.89 %) and N2O (20.05 %) emissions, and increased humus content (16.22 %). Mantel analysis showed that the higher abundance of nitrifying bacteria and nxrA facilitated the nitrification of NH4+-N. The improvement in nitrite oxidoreductase activity promoted NO3–-N formation, leading to increased humus content and enhanced compost safety.

Effects of exogenously added humic acid on the fate of aminoglycoside antibiotics and humification process during aerobic compost

Efficient elimination of antibiotics, particularly aminoglycosides, and Antibiotic resistance genes (ARGs) from agricultural and livestock waste, as well as enhancing the level of humification, remains a major challenge in the pursuit of high-value utilization of agricultural waste. Here, the roles of bacteria and fungus in the dissipation of aminoglycoside antibiotics, ARGs and the enhancement of humification with the addition of humic acid (HA) to compost systems were investigated. Compared to the control, the contents of humus (HS) and HA were increased by 41.3 and 143.3 %, respectively, and the content of fulvic acid (FA) was decreased by 74.1 % with HA addition. Interestingly, the abundance of aminoglycoside ARGs was decreased significantly (p < 0.05) as well as the abundance of functional genes involved in oxidative stress response and type IV secretion system (T4SS). The bacterium Nocardiopsis related to carbon cycle, and the fungi Ascomycota and Basidiomycota associated with ligocellulose degradation were significantly enriched (p < 0.05). Structural equation models revealed that the decrease in aminoglycoside ARGs abundance was attributed to bacteria promoting HA synthesis, thereby inhibiting the multiplication of aminoglycoside ARGs and ultimately mitigating oxidative damage to microbial cells. These findings shed light on the mechanism by which HA removes aminoglycoside ARGs, and provide valuable insights into enhancing the biosafety of compost products.

Evaluation of the Informative Value of the Results of Soil Observations in a Stationary Experiment

The effective and potential fertility of leached chernozem was evaluated in a field stationary experiment at the Central Experimental Field of the Kurgan Research Institute and the application of 2 crop cultivation technologies. In the first part of the experiment, the corn–wheat–wheat–oat crop rotation was studied during annual plowing, in the second – permanent wheat after a stubble background. The first technology was characterized by higher effective fertility, a large number of plant residues, due to which its advantage was manifested in terms of humus content. The positive effect of fertilizers on the indicators of potential soil fertility was manifested when applying the 2nd and 3rd doses of nitrogen against the background of the use of phosphorus.

Продуктивность пивоваренного ячменя в зависимости от приёмов основной обработки почвы и регулятора роста Моддус

In modern conditions, the most effective way to increase the gross production of spring barley is to select the most productive varieties and realize their potential productivity by improving the technology of cultivation of spring barley for specific soil and climatic conditions of the zone. In this regard, the improvement of the complex of agricultural practices that increase the yield of barley is relevant and of particular scientific and practical interest. The purpose of the research was to improve the techniques of basic tillage and the use of growth regulators in the cultivation of spring malting barley. The research was conducted from 2022 to 2024 in the Moscow region at the experimental field of the Federal Research Center "Nemchinovka". The soil is sod-podzolic, heavy loamy. pH is 5.4 units. The humus content is 1.7%. As a result, on average for 2022-2024, observations of the spread of weeds in malting barley crops found that the smallest number of all weeds was fixed on the variant of chisel processing by Ranch workers with pruning paws to a depth of 0.27-0.30 m and amounted to 154 pcs/case. The highest height of brewing barley plants of the Reliable variety on average for 2022-2024 turned out to be on the variant of chisel tillage m without the use of growth regulators and was 69 cm. The largest number of productive stems was established on the variant of chisel tillage to a depth of 0.27-0.30 m without the use of a growth regulator and amounted to 498 pcs./m2, that is, 51 pcs./m2 more than the lowest value. The largest grain mass in the ear was set on a variant of chisel tillage to a depth of 0.27-0.30 m using the growth regulator Moddus CE at a dose of 0.4 l /ha and was equal to 1.25 grams, that is, 0.17 grams more than the lowest value. The highest yield was also formed on the variant of chisel processing by the working body of the Ranch with pruning paws to a depth of 0.27-0.30 m using the growth regulator Moddus CE at a dose of 0.4 l /ha and averaged 6.10 t/ha.