Soil Humus Research Articles

Soil technogenic radioactivity in the vicinity of the Morzhovets Lighthouse (the Morzhovets Island, Archangelsk region)

The aim of the study was to assess soil technogenic radioactivity in the vicinity of the Morzhovets Lighthouse and surrounding areas by measuring radio caesium (137Cs) specific activity. Location and time of the study. Field work was performed in the area around the Morzhovets Lighthouse (the Morzhovets Island, Archangelsk region) in summer 2022. Methods. Soil samples were collected at 26 sites from the 0-5 cm layer, of which at 12 sites soil samples were collected also from 5-10 и 10-20 cm layers. Aboveground phytomass was sampled as well. In the laboratory the soil samples were air-dried and placed in the Marinelli vessel for measuring 137Cs specific activity by gamma-spectrometry. Registration of the gamma-radiation from the measured soil sample, as well as processing of the obtained spectra were performed using the Progress-gamma software and hardware complex FVKM.412131.002-03. The energy calibration of the gamma spectrometer to control the safety of the setup parameters was carried out after each measurement using a combined control source OISN-137-1 in a Marinelli vessel. The minimal exposure time of the study sample was 3600 sec; however, the time was increased for some samples with low activity. Results. The territory of the Morzhovets Island is occupied by the lowland seaside terraced plane landscapes with tundra vegetation on the peaty podsolised illuvial humus soils, alternating with mires. Caesium specific radioactivity in the top 0-5 cm soil layer, represented by poorly decomposed peat horizon, was found to vary from 9.4 to 144.5 Bq/kg in the peaty illuvial-humus podzol (Gleyic Histic Entic Podzol) and from 12.2 to 139.4 Bq/kg in the bog peat gley soils (Fibric Histosols (Gleyic)). The radio caesium specific activity was shown to decrease sharply with soil depth, reaching the 3 Bq/kg detection limit of the gamma-spectrometer. Comparative analysis of the data showed that in the West Arctic sector 137Cs specific activity decreases from the east to the west, with increasing distance from the Novaya Zemlya, from 80.2 Bq/kg (the Novaya Zemlya Archipelago) and 80.7 Bq/kg (Bolshezemelskaya Tundra) to 19. 2 Bq/kg (the Svalbard Island). Conclusions. The 137Cs distribution in soil of the Morzhovets Island showed the persistent fixation of the element by the upper 5 cm-thick organic part of the soil profile, representing the primary biogeochemical barrier. The vegetation does not accumulate technogenic radioactivity. Overall, the 137Cs distribution in soils around the Morzhovsky Lighthouse displays a medley pattern. The maximal 137Cs specific activity values were measured both in the peaty illuvial-humus podzol and bog peat gley soils.

Mineral-associated soil organic matter: characteristics and behavior under diagenesis

The main part of soil organic matter (OM) is mineral-associated: 88 ± 11% of С and even more – 93 ± 9% of N. The aims of the given study were: 1 – to demonstrate experimentally the adsorption selectivity of organic compounds towards minerals with different physico-chemical properties (palygorskite vs montmorillonite); 2 – to characterize mineral-associated OM of buried Late Holocene palaeosols and estimate its diagenetic transformations; 3 – to investigate the OM of humin from modern soils of different genesis and Pleistocene and Holocene palaeosols and estimate its diagenetic transformations. The basic soil properties were determined using standard methods. Clay fractions (<2 um) – natural organo-mineral complexes (OMC) were obtained by sedimentation, their mineralogy was studied by XRD. The elemental composition of OM was studied with CNS-analyzer. The structural characteristics of organic matter were determined with the solid-state 13C-NMR-spectroscopy and FTIR-spectroscopy, isotopic composition of C and N – by mass-spectrometry. The obtained results show that the characteristics of mineral-associated OM depends on the properties of mineral “filter” as well as the fate of OM under diagenesis: how long, in what quantity and quality it will persist. It was shown that palygorskite adsorbed predominantly O-alkyls, which are chemically strongly bound. As a result, the age of fulvic type humus in palygoskite palaeosols can reach 300 My. From other side humus of smectitic paleosols of the same age is present by deeply transformed aromatic structures (“coal”). Mineral-associated OM of buried under kurgans Holocene palaeosols contains more alkyls and carboxylic groups, is less aromatic in a comparison with OM of the respective soils. The specific feature of mineral-associated OM is its enrichment in N-compounds. The later are present by both vegetal and microbial compounds, and demonstrate the large affinity towards the mineral surfaces. The formation of chemical bounds between them provides the persistence of OM in OMC. E.g. H2O2 treatment results in preferential destruction of C-rich compounds and oxidized OM demonstrates larger C/N values. Mineral-associated OM of buried Holocene soils keeps the decreased values of C/N (7–14 vs 14–21 for OM of whole soils). Additionally they are characterized by heavier isotopic composition of δ15N in a comparison with the respective soils (5–11‰ vs 6–9‰). It could be explained either by the accumulation of microbial N, or increasing of the humification degree – the loss of aliphatic C and increasing of aromaticity. Humin is the considerable part of soil humus. Experimentally shown that OM of humins both of soils and OMC is enriched in O-alkyls and C of acetal groups. OM of humins are not homogeneous, and consists from at least two groups: mineral-associated OM and partly mineralized plant fragments. As a consequence, the content of humin in OMC is smaller in a comparison with respective soils. It is concluded that mineral-associated OM and humin as well as soil humus represent dynamic soil systems.

Complementary ESI and APPI high resolution mass spectrometry unravel the molecular complexity of a soil humeome

High resolution mass spectrometry (HRMS) can resolve thousands of compounds in complex mixtures such as natural organic matter. However, HRMS is seldom sufficient to fully resolve the molecular heterogeneity of Humus in the soil matrix, especially if no preliminary simplification of Humus complexity is applied and if a single ionization technique is used. Here we show that HRMS, when applied with both photoionization (APPI) and electrospray ionization (ESI) and combined with the extensive molecular simplification provided by a humeomic fractionation, significantly increases identification of the molecular composition of soil Humus. Different sequential extractions separate the soil Humeome in three organosoluble fractions (ORG1-3) and two hydrosoluble fractions (AQU2 and RESOM), which showed distinct molecular characteristics. The ORG fractions were particularly homogeneous and rich in alkyl compounds including unsaturated hydrocarbons and lipid compounds found mainly in ORG 1 and ORG 3, but also aromatic compounds comprising lignin-like molecules and condensed structures mainly detected in ORG2. The AQU2 fractions revealed greater complexity and heterogeneity due to the simultaneous detection of sugars, amino sugars, tannins and N-containing compounds not detectable in appreciable concentrations in other fractions. The most recalcitrant RESOM fraction contained highly reduced molecules and condensed structures. The combined use of APPI and ESI showed a marked selectivity in the detection of chemically different molecules separated in each fraction, thereby enhancing their molecular characterization. Specifically, APPI tended to ionize less oxidized and N-containing molecules, and compounds with high concentrations of unsaturation or aromatics, while ESI was more prone to detect highly oxidized compounds consisting of large O/C ratios. Our findings indicate that the combination of a soil Humeome fractionation with a detailed high resolution characterization of differently ionized molecules in the separated fractions enables a far deeper understanding of the molecular composition of soil Humus and the comprehension of its environmental reactivity.

APPLICATION OF VEGETATION INDECES FOR DOGITAL SOIL MAPPING BASED ON SENTINEL-2 SPACE IMAGES

At present, the works devoted to the creation of digital soil maps using geographic information systems (GIS) and remote sensing (RS) data are relevant. In the work the analysis of vegetation indices (VI) for soil mapping was carried out, the maps of vegetation indices were created: Normalized Difference Vegetation Index (NDVI), Optimized Soil-Adjusted Vegetation Index (OSAVI), Soil-Adjusted Vegetation Index (SAVI), Tranformed Soil-Adjusted Vegetation Index (TSAVI), Enhanced Vegetation Index2 (EVI2) for the territory of ZAO Mirny farm of Kochenevsky District using Sentinel-2 A satellite image (May 10, 2021). ). As a result it was revealed that the vegetation indices OSAVI and EVI2 allow to establish spatial boundaries between the main types of soils of automorphic, half-hydromorphic and hydromorphic moisture regimes.
 Background. Multispectral space and aerial photos for thematic mapping of soil resources are of greater practical application. Sentinel-2 A space image with good spatial and spectrozonal resolution (10 m, 20 m and 60 m) and territorial coverage (290 km) was used in this article. This made it possible to calculate and analyze various vegetation indices for the purposes of digital soil mapping.
 Purpose. аnalysis of vegetation indices for digital soil mapping based on Sentinel-2 A images.
 Materials and research methods. The research was carried out on the territory of CJSC Mirniy, Kochenevsky District, Novosibirsk Region. The methods of digital processing of space images, mapping and geoinformation analysis with the use of Sentinel-2 A satellite image (May 10, 2021) were used. The method of equal intervals was used for comparative analysis of images. This allowed using GIS ArcGIS to make thematic maps of images with the allocation of gradations: very low, low, average, above average, high value.
 Results. Field soil surveys were carried out on the territory of CJSC Mirny farm in Kochenevsky district of Novosibirsk Region. Using SAGA geoinformation system the space image was atmospherically corrected and spatially referenced, NDVI, OSAVI, TSAVI, EVI2 raster maps were compiled. Geoinformation analysis of the large-scale 1:1000 soil map and raster EVI maps revealed that OSAVI allows to establish spatial boundaries between the main types of soils of automorphic, half-hydromorphic and hydromorphic moisture regimes. Very low values of VI are typical for the soils of hydromorphic humidification regime, formed near small lakes, along the banks of the Sharikh river.
 Very low values of UI have objects of hydrography, marsh peaty, meadow-marsh humus soils, marshy and peated marshes, marsh solonchaks, marsh solonchaks, formed in lowered areas of relief with depth of groundwater occurrence less than 0.5 m.
 Ploughed ordinary chernozems, deposited in the upper and middle part of the gentle slope, have low values of WP. These are soils of automorphous moisture regime with depth of groundwater occurrence more than 6 m.
 Average and above average values are characteristic of gray forest saltwort soils under woody vegetation, as well as meadow-chernozem soils under meadow vegetation in the lower part of the gentle slope with groundwater occurrence depth from 3 to 4 m. High WI values were obtained for meadow soils with dense grass cover. Wetting conditions of soils, location in the relief, and vegetation type significantly influence VI values. The obtained VV values can be used at the stage of training data preparation in the form of reference classes for basic soil types required for automatic image recognition.

Design and Build a Soil Nutrient Measurement Tool for Citrus Plants Using NPK Soil Sensors Based on the Internet of Things

A suitable planting medium is a medium of good quality soil that can support plant growth quickly. Fertile soil is the primary need for plants. The quality of the planting medium dramatically affects plant growth. The types of soil needed for plant growth vary, namely sandy soil, red soil, alluvial soil, and humus soil. Using an NPK sensor that functions to detect nutrients in the soil and can work if the tip of the sensor is plugged into the soil they want to detect, the results detected by the sensor will be sent in the form of analog signal data to nodemcu, which will be processed and displayed on the screen. Thingspeak. This tool is controlled by nodemcu with an NPK sensor to detect nutrients in the soil with output to thingspeak. The function of the NPK sensor tool will measure the nutrients in the soil for citrus seedlings, and the results read by the Npk sensor will be sent to the Thingspeak web, making it easier for farmers to seed citrus seeds. The data read by the sensor will be sent to thingspeak, making it easier to monitor nutrients in the soil. From the results of the tests carried out, it is found that the nutrient content in wet soil is higher than in dry soil; from the tests carried out, the NPK sensor accuracy rate is 90%.

STUDY OF TRITIUM MIGRATION AND RETENTION MECHANISMS IN THE GEOLOGICAL ENVIRONMENT (BY THE EXAMPLE OF THE KYIV RADIOACTIVE WASTE STORAGE FACILITY)

Radioactive waste storage facilities (RWSF) are a potential source of tritium in the biosphere. Engineered concrete constructions are not sufficiently reliable forasmuch as water leaks contaminated with tritium from the storage facilities into the geological environment has been detected. The barrier properties of the natural environment at the storage sites are determined by the ability to absorb and retain heavy isotopes of hydrogen during a considerable period of time and thus exclude its circulation in the biosphere. Various elements of the natural ecosystem take part in the absorption of tritium – the geological environment, soil organic matter, annual and perennial vegetation, micro- and macrobiota. A certain part of tritium in the gaseous and aerosol form is released into the air. The highest concentrations of tritium are recorded in the area close to the concrete radioactive waste (RW) storage facilities, where the vapor-gas emanation plume is least dispersed. With distance from the storage facilities, the tritium concentration in the soil humus layer significantly decreases due to the spatial dispersion of the tritium in the atmospheric plume. Tritium from the air enters the soil with the atmospheric precipitation and is partially retained in the humified layer of the soil. Most of the tritium from the atmospheric precipitation is transported by the vertical infiltration flow through the sedimentary layers represented by loess sandy loams and loams, where it is finally retained. In the area close to RWSFs, the concentration of heavy hydrogen isotope in pore, interstitial and film water (1 fraction) is up to 87 % of its total content in an elementary block. In the more tightly bound forms (2 and 3 fractions), it is 9 % and 4 %, respectively. Farther from the RW storage facilities in the predominant air flow direction, the tritium concentration in free water decreases to 75 %. In this area, more intensive redistribution of tritium between the structural sites is observed. At the more distant monitoring points (wells), from 25 % to 37 % of the total tritium amount in the soils is retained in more tightly bound forms in the structure of rock-forming, mainly clay minerals

Influence of manure application method on gray forest soil fertility, crop yield and quality

The article presents the results of field experiments on deepening the arable horizon of gray forest medium loamy soil to increase its fertility through applying organic fertilizer under PY-3-35 layer plow to a depth of 2527 cm. Low mineralization of organic fertilizer during layer cultivation under oxygen deficiency conditions contributed to accumulation of humus in soil by 6.6 t/ha more than during conventional plowing, and by 7.5 t/ha - than during disking. It also improved water-physical and biological properties of soil: number of water-resistant aggregates increased by 4.6 and 5.3 %, soil density lowered by 0.03 and 0.04 g/cm3, number of earthworms increased by 3...6 individuals, expanded reproduction of fertility was provided, productivity of arable land increased by 7.0 and 6.7 % and crop quality increased compared to conventional plowing and disking, respectively. Deep manure incorporation extended life of organic fertilizer up to 5 years, while after conventional plowing and disking this process lasted only 2...3 years. It is not economically and environmentally beneficial, since frequent application requires a lot of fuel, and a large amount of harmful chemical compounds contained in combustion products is dumped into the environment.

Differential Variation in Non-structural Carbohydrates in Root Branch Orders of Fraxinus mandshurica Rupr. Seedlings Across Different Drought Intensities and Soil Substrates.

Non-structural carbohydrates (NSCs) facilitate plant adaptation to drought stress, characterize tree growth and survival ability, and buffer against external disturbances. Previous studies have focused on the distribution and dynamics of NSCs among different plant organs under drought conditions. However, discussion about the NSC levels of fine roots in different root branch orders is limited, especially the relationship between fine root trait variation and NSC content. The objective of the study was to shed light on the synergistic variation in fine root traits and NSC content in different root branch orders under different drought and soil substrate conditions. The 2-year-old Fraxinus mandshurica Rupr. potted seedlings were planted in three different soil substrates (humus, loam, and sandy–loam soil) and subjected to four drought intensities (CK, mild drought, moderate drought, and severe drought) for 2 months. With increasing drought intensity, the biomass of fine roots decreased significantly. Under the same drought intensity, seedlings in sandy–loam soil had higher root biomass, and the coefficient of variation of 5th-order roots (37.4, 44.5, and 53% in humus, loam, and sandy–loam soil, respectively) was higher than that of lower-order roots. All branch order roots of seedlings in humus soil had the largest specific root length (SRL) and specific root surface area (SRA), in addition to the lowest diameter. With increasing drought intensity, the SRL and average diameter (AD) of all root branch orders increased and decreased, respectively. The fine roots in humus soil had a higher soluble sugar (SS) content and lower starch (ST) content compared to the loam and sandy–loam soil. Additionally, the SS and ST contents of fine roots showed decreasing and increasing tendencies with increasing drought intensities, respectively. SS and ST explained the highest degree of the total variation in fine root traits, which were 32 and 32.1%, respectively. With increasing root order, the explanation of the variation in root traits by ST decreased (only 6.8% for 5th-order roots). The observed response in terms of morphological traits of different fine root branch orders of F. mandshurica seedlings to resource fluctuations ensures the maintenance of a low cost-benefit ratio in the root system development.

Сукцессии микробиотических сообществ песчаных почв в разновозрастных сосновых насаждениях лесостепной зоны

Peculiarities of transformation processes in soils should be taken into account when developing strategies for their rational use and optimization of their functions. The purpose of the work is to study the successions of soil microbiotic coenosis of azonal Al-Fe-humus sandy soils in pine forest stands of different age in the cities of the Kursk region. Traditional and innovative methods of studying the microbiological activity of soils are used in the work. Al-Fe-humus sandy soils of the forest-steppe covered with 100-year-old stands of Scots pine emit 2.1-2.3 times more CO2 than Al-Fe-humus sandy soils under 25 - and 70-year-old stands of pine and 1.5 times more than similar soils under herbaceous phytocenoses. It has been established that stands of Scots pine during 100 years of vegetation lead to significant changes in the basic properties of soils, changes in response, increase in podzolic process, changes in hydrothermal conditions, as well as increase in the biomass of the main groups of soil microorganisms (up to 38.1 times). Keywords: MICROMYCETES, ACTINOMYCETES, SANDY PODZOLS, GRAY HUMUS (TURF) SOILS, CO2 EMISSION, MICROBIOLOGICAL ACTIVITY OF SOILS

Microbiological Degradation of Poly(3-Hydroxybutyrate) Films in Different Edaphoclimatic Zones of Siberia

The urgency of handling plastic waste is escalating every year and the problem can be only solved using an integrated approach. Replacing non-degradable materials synthesised from fossil fuels with carbon-neutral biopolymers can reduce non-biodegradable waste, CO2 emissions and energy use. However, even completely biodegradable biopolymer materials will stay in the environment for a long time since the rate of their biodegradation depends on many factors. The paper evaluates the influence of edaphoclimatic and microbiological factors on the biodegradation rate of biopolymer films from the poly(3-hydroxybutyrate) [P(3HB)] when exposed to soddy-carbonate, cryogenic, and agrogenically transformed Siberian soils. A principal component analysis showed that in different soils, characterised by specific temperature, moisture content, pH values, biogenicity and abundance of microorganisms, the kinetics of mass loss of P(3HB)-films were primarily determined by the temperature- precipitation ratio and it increased as the content of humus in soil increased. The maximum rates of film mass loss of 0.63 ± 0.09 and 0.93 ± 0.01 mg ∙ day-1 were detected in agrogenic soils. No correlation between mass loss of the films and the total number of microorganisms was found. A phylogenetic analysis revealed differences in the composition of primary P(3HB)-degrading microorganisms in different soil types

Modelling soil organic carbon turnover with assimilation of satellite soil moisture data

The content of organic carbon is one of the essential factors that define soil quality. It is also notoriously challenging to model due to a multitude of biological and abiotic factors influencing the process. In this study, we investigate how decomposition of soil organic matter is affected by soil moisture and temperature. Soil organic carbon turnover is simulated by the CENTURY model. The accuracy of soil moisture data used is ensured by data assimilation approach, combing mathematical model and satellite retrievals. Numerical experiments demonstrate the influence of soil moisture regimes and climate on the quantity of soil humus stocks.

CONTRIBUTION TO KNOWLEDGE ON THE VARIABILITY OF AROLLA PINE WOODLANDS OF THE NORTH-EASTERN TATRA MOUNTAINS

Knowledge of the overall syntaxonomic and habitat variability of forest communities with Arolla pine (Pinus cembra) within the Tatra Mountains (Western Carpathians) is still insufficient as field research was hindered by their hardly accessible localities and deforestation for high mountain grazing. Arolla pine woodlands were traditionally classified within the association Pino cembrae-Piceetum Myczkowski et Lesinski 1974, but recent surveys recognize more numerous units. Hitherto unpublished releves from the north-eastern part of the Tatra Mountains document the occurrence of several floristically and ecologically distinct Arolla pine communities: (1) acid woodland of Homogyno alpinae-Pinetum cembrae on nutrient-poor habitats over quartzitic bedrock, and (2) calcareous woodlands of species-poor Pyrolo rotundifoliae-Pinetum cembrae of sites with a well-developed, tangled humus soil horizon, Cystopterido montanae-Pinetum cembrae on habitats influenced by both limestones and quartzites, Primulo elatioris-Pinetum cembrae bound to sites with the most favourable humidity, and Seslerio tatrae-Pinetum cembrae with the most pronounced calcareous character.

Агроінженерні підходи щодо збереження родючості ґрунтів

Goal. To analyze possible agro-engineering ways to stop the rapid fall and to ensure further preservation of humus in agricultural soils. Methods. Analysis and synthesis of scientific results contained in domestic and foreign literature on agriculture. Laboratory and field experiments aimed at determination of the structure of the soil at different levels of slippage of the engines of the aggregate tractor and provision of the ecophilicity of the tires of its running wheels were carried out using modern methods of multifactor experiment, the latest recording equipment, modern methods of statistical processing of research materials on PC. Similar methods of experimental researches were applied at carrying out laboratory field tests of wide-reaching and combined machine-tractor units, including technologies with the use of a constant technological track. Results. Intensive processes of humus destruction are considered, which significantly affect the preservation of the structure of agricultural soils. Specific measures and technological and organizational solutions that allow overcoming this complex and incessant phenomenon with the use of exclusively agro-engineering approaches are outlined. Conclusions. The process of preserving the structure of agricultural soils requires urgent adoption of technological and organizational decisions aimed at: maximum restriction of soil nitrogen immobilization after wrapping organic residues in it; development of technological methods and tools for tillage for loosening the surface layer of the soil with a minimum area of its contact with the air-drip medium; improvement of the basics of aggregation of agricultural machines/tools taking into account the maximum allowable slippage of wheeled energy means at the level of 15% and the conceptual approach to their ballasting in relation to the requirements of ecophilicity of tires; application of the soil structure indicator when determining the periodicity of plowing with plows with plowshares or their two-levelled analogues; wide practical application of track system of agriculture (Controlled Traffic Farming); adoption of a legislative document on the specific responsibility of land users for the level of fertility of agricultural soils.

Influence of humic preparations on productivity increase of cucurbits in arid farming conditions

The paper presents the results of studying the influence of liquid humic fertilizer produced from milled lowland peat on biological activity, the dynamics of nutrients in brown semi-desert soils in arid climate conditions with leaf fertilization of cucurbits. In arable farming of the Astrakhan region most of the harvest is formed by mobilizing soil fertility without compensation for the elements of nutrition carried out with the harvest, which leads to a negative balance of humus and nutrients, as a consequence, the soil is depleted, its fertility becomes lower. It is shown, that application of humates promotes increase of the content of humus in soil in arable horizons and reception of higher harvests of an early ripe watermelon that is caused by activization of biochemical processes in soil and increase of nutrients availability that has accelerated development and ripening of fruits of studied crop.

Influence of Method, Duration and Norms of Application of Logon Minefield Bentonite Mud on the Amount of Nutrients in the Soil

The article discusses the impact of the application of bentonite sludge from the Logan deposit in different methods, terms and standards on the nutrients in the soil in the conditions of meadow saline, moderately saline soils of Central Fergana.As a result of application of Logan bentonite mud under autumn plowing at the rate of 1.5-3.0 t / ha per year, in three years in the driving layer of the soil humus 0.003-0.007%, total nitrogen 0.002-0.006%, phosphorus 0.005-0.015%, potassium 0.012-0.030 % increase and reports of improved agrochemical properties

Distribution, nature and threats to soils of the Australian Alps: A review

AbstractThe Australian Alps contain an assemblage of soil types that is unique on the Australian continent. The above‐ground ecosystems of the Australian Alps have received considerable scientific attention but research relating to the nature of its soils has been much more limited. A fuller understanding of the role of soils in these ecosystems is required to inform effective management strategies. This review was undertaken to assess existing research on soils in the Australian Alps. We aimed to summarise our current knowledge of their nature, distribution and characteristics, to examine the services they provide and to assess their vulnerability to the range of threats that exist to the soil resource both local and external. Soils of higher elevations, namely Transitional Alpine Humus Soils, Alpine Humus Soils and upland Peat Soils are particularly important to the ecology, hydrology and potential carbon storage of the region, yet our understanding of the nature, formation and functioning of these soil types remains weak. A series of knowledge gaps and research priorities are identified, relating to basic knowledge needs on the formation, distribution and function of these soils, particularly their microbial populations and the impacts of specific threats (i.e. climate change, grazing, fire, visitors, infrastructure, feral animals and pollution).

Balance of the territorial organization of agricultural landscapes of the eastern division: scientific-methodical and practical approaches

«Sustainable Development Strategy of Ukraine until 2030» provides for the introduction of effective and scientifically sound methods of agricultural production, which would contribute to the preservation of agro-ecosystems, increase their adaptive capacity to withstand climate change (adverse weather events, droughts, floods), improve environmental lands and soils. However, without the balance of the territorial organization of the state of agricultural landscapes it is impossible to achieve this goal. We analyzed the balance of the territorial organization of modern agricultural landscapes of Eastern Podillya, which is 4.4% of the total area of Ukraine, where the share of the region in total agricultural production is 12.3%. Currently, the main destabilizing factors of agricultural land in the structure of agricultural landscapes of Eastern Podillya are: high plowing of agricultural land (average in the region is 75.2%), low level of humus in soils (2.7%), insufficient levels of nutrients (nitrogen 82.0 mg/kg, phosphorus 83.5 mg/kg, potassium 109.9 mg/kg), practically no crop rotations (53% are occupied by cereals and legumes, 32% by industrial crops, 8% by potatoes and vegetables). According to our calculations, it has been established that part of the land of district communities belongs to the ecologically unstable or stably unstable category of land. The lowest level of environmental stability is observed in the central and south-eastern communities. For further balanced development of agrolandscapes of the East Podolsk region, scientific-theoretical and practical approaches to the functioning of agroecosystems are substantiated and a set of measures to comply with the environmentally friendly state of agricultural land use is proposed. The priority areas of balan­cing the territorial organization of agro-landscapes of the region and improving their ecological condition are measures of regulatory, institutional, technical and economic and organizational and land management. Observance of these measures will provide an opportunity to use significant reserves to increase agricultural production, ensure significant «rehabilitation» of agricultural landscapes and improve the living conditions of the rural population.

The Role of Laccase from Zygomycetous Fungus Mortierella elasson in Humic Acids Degradation

Biochemical stability of soil humus is an important factor affecting soil quality. Fungi are among the most efficient decomposers of humic matter due to presence of oxidative enzymes, including phenoloxidase laccase. Production of laccase by zygomycetes, a group of cellulolytic fungi widespread in soil, is poorly studied. The potential role of laccase from zygomycetes in humus turnover is unknown. Here, we show for the first time that laccase of zygomycetous fungus Mortierella elasson can effectively depolymerize humic acids in vitro. The fungus produced laccase extracellularly in a liquid culture medium. Unlike in case of laccases in ligninolytic basidiomycetes, attempts to increase enzyme activity using inductors, changes in the source of nitrogen and carbon failed to lead to any increase in laccase production. Laccase was purified using ion exchange chromatography and gel filtration. The molecular weight of the laccase was 51.75 kDa. The laccase catalyzed the oxidation of ABTS and K4[Fe(CN)6], phenolic compounds, but not tyrosine. The laccase activity was inhibited by NaN3 and NaF. The pH optimum of the laccase activity was 3.0 for ABTS and 5.0 for 2,6-dimethoxy phenol. The enzyme had moderate thermal stability and was rapidly inactivated at 70 °C. Purified laccase depolymerized humic acids from retisol, compost and peat more effectively than culture liquid containing laccase. The results of the study extend our knowledge of the role of laccases from different producers in the transformation of natural organic matter.

Analysis of The Relationship Between Microbial Activities In Humus Soil Towards Infiltration Rate for Fertility Improvement With Biosoildam Technology for Corn Plantation

Analysis of The Relationship Between Microbial Activities In Humus Soil Towards Infiltration Rate for Fertility Improvement With Biosoildam Technology for Corn Plantation

Influence of using fertilizers on fertility indices of sod-podzolic soils and productivity of short-term crop rotation of Polissya

The influence of litter manure and straw as fertilizers in pure form and in combination with manure, green manure and mineral fertilizers on the content of humus and basic nutrients in sod-podzolic soil has been studied. A significant effect on the change of humus content on sod-podzolic soils depending on fertilizer systems has been established. The highest indicators of humus content in the soil were found in the variants with 40 t/ha of manure, 0.97–1.14% and 1.17–1.23%, respectively, and straw 4 t/ha in combination with lupine green manure — 0.94–1.15% and 1.16–1.25%. The most significant increase in humus content per rotation was observed in sidereal crop rotation, against the background without fertilizers the indicator increased by 0.05–0.29%, against the background of N40P40K120 application — by 0.03–0.21%, in crop rotation — 0.05–0.19% and 0.01-0.09%, respectively. Analyzing the dynamics of the content of easily hydrolyzed nitrogen, it was found that the greatest growth both at the beginning and at the end of crop rotation provided options with the introduction of 40 t/ha of manure (+69…+85 mg/kg of soil), 4 t/ha of straw with half dose of manure (+63…+82 mg/kg of soil) and straw with green manure (+71…+80 mg/kg of soil). The application of manure, straw and plowing of green manures contributed to the increase of the content of mobile phosphorus compounds from 9 to 69 mg/kg of soil on the background without fertilizers and 38 to 67 mg/kg of soil on the background N40P40K120. The combination of straw with manure and straw with green manure for the application of mineral fertilizers helped to increase the content of mobile phosphorus compounds to the level recorded in the variant for the application of 40 t/ha of manure, and in some versions of the experiment even exceed it. It was found that the deficit-free and positive balance of potassium for rotation of crop rotation and sidereal crop rotation was provided by variants with 4 t/ha of straw in combination with 20 t/ha of manure and 4 t/ha of straw in combination with lupine green manure against N40P40K120. Balances and productivity of arable land use in short-rotation crop rotations of Polissya are calculated. In crop rotation, the humus balance is negative for the alienation of lupine green mass for fodder. Variants with application of 10 t / ha of crop rotation area of manure (–0.03 t/ha) and 1 t/ha of straw with half dose of manure (–0.1 t/ha) on the background of N35P35K85 application allowed to get as close as possible to the deficit-free balance of humus. In sidereal crop rotation, a positive balance of humus is observed with the application of 10 t/ha of manure (+0.21…+0.29 t/ha), 1 t/ha of straw in combination with 5 t/ha of manure, 22 t/ha) and 1 t/ha of straw in combination with green manure (+0.09… +0.18 t/ha). Close to the deficit-free balance of humus is the option with the introduction of 1 t/ha of straw in its pure form. An alternative to manure in Polissya should be the use of straw in combination with green manure (including lupine), which will help preserve and reproduce the humus content in the soil, improve the balance of nutrients and increase the productivity of arable land in crop rotations.