Lubica Pospíšilová

Sustainable management of permanent grasslands requires evidence-based selection of fertilization practices that support long-term soil organic matter quality and ecosystem function. This study addresses the need to identify optimal agricultural practices in permanent grasslands and the effects of organic and inorganic fertilizers on soil humic substances (HS) composition and stability. Grassland plots were amended after cutting with mineral fertilizer (NPK), farmyard manure (FYM), cattle slurry (CS), or digestate (DIG), and humic acids (HA) were isolated using the standard International Humic Substances Society procedure. The elemental composition, total carbon and nitrogen contents, C/N ratio, and selected biogenic elements were determined using routine laboratory methods, while infrared spectroscopy, fluorescence excitation–emission matrix analysis, and electron paramagnetic resonance spectroscopy were applied to characterize chemical structure and semiquinone radical concentrations. Principal component analysis (PCA) indicated distinct clustering of fertilization treatments, which was supported by a statistically significant effect (p < 0.05) based on ANOVA. The results suggest that the fertilization regime was associated with variation in HS composition and radical abundance. DIG and NPK treatments showed lower O/C ratios and radical concentrations, potentially reflecting more reduced humic acids. In contrast, FYM and CS treatments tended to exhibit higher radical concentrations and O/C ratios. These findings highlight the importance of fertilizer type in shaping soil organic matter dynamics in managed grassland ecosystems and provide a scientific basis for the development of sustainable soil management strategies and environmentally sound fertilization practices in permanent grassland systems.

Changes in the chemical composition and stability of humic substances after soil amendment with mineral and organic materials were studied. The study site, a Gleyic Fluvisol (Jaroměřice locality, Pardubice Region, Czech Republic), was under permanent grassland managed intensively (four cuts per year) and fertilised as follows: manure and slurry at a rate of 2 livestock units = 120 kg N per ha. The fertilisation treatments included: C – control (no fertilisation); FYM – farmyard manure (30.0 t ha-1); CS – cattle slurry (29.0 t ha-1); DIG – digestate (29.0 t ha-1); NPK – mineral fertilizer (120-30-60 kg ha-1). The study aimed to evaluate changes in the structural composition and stability of humic substances during the period 2022–2024, with the goal of providing a knowledge base for farmers to develop best practices for maintaining soil carbon stocks under intensive agricultural conditions. Humic substances (humic and fulvic acids) were extracted with a mixture of 0.1 M NaOH and 0.1 M Na4P2O7 /1:1, w/w. Further, humic acids (HA) were isolated according to the standard IHSS method and characterized using UV-VIS and DRIFT spectroscopy. Calculated indices showed higher HA stability and wettability after FYM, DIG, and CS application in comparison with NPK and control. The differences were found in the content of labile aliphatic hydrophobic groups (at 3000–2800 cm-1), aromatic stable and resistant C=C groups (at 1660–1580 cm-1), and hydrophilic amido-, carboxylic-, keto-groups (at 1740–1600 cm-1). The amount of hydrophilic resistant groups at 1660–1580 cm-1 was comparable at all sites. DRIFT and UV-VIS spectral methods were proposed as rapid tools for assessing humic substance quality instead of the laborious and time-consuming classical fractionation method.

Water erosion significantly affects soil properties, yet comparative studies between different soil types are limited. This study examines the impact of erosion on the physical, chemical, and biochemical properties of Chernozems and Cambisols in the South Moravian and Vysočina regions of the Czech Republic. We combined field sampling, laboratory analysis, and geospatial modeling to identify erosion, transition, and deposition zones on slopes. Soil samples were collected from these zones in both soil types and analyzed for particle size distribution, organic carbon content, humus quality, stability of aggregates, pH, nutrient levels, enzyme activities, and glomalin content. Chernozems showed more pronounced differences between the erosion and deposition zones, particularly in organic matter content, nutrient levels, and enzyme activities. Cambisols exhibited different patterns, with less pronounced differences between the zones, except for humic substances and cellulase activity. Chernozems had higher carbonate content and pH in erosion areas, while Cambisols showed an opposite trend. These differences relate to both substrate and slope shape: concave–convex for Chernozems and convex to convex–concave for Cambisols. The findings highlight the importance of considering soil type and topography in erosion studies and have significant implications for tailored soil management and erosion control strategies in different agricultural landscapes.

Soil organic matter and pores distribution within aggregates were studied using X-ray computed tomography (XCT; Nikon XT H 225ST and GE Phoenix L240) and advanced 2D/3D measurements by?the digital Keyence VHX-6000 microscope (Japan). A?new met...

Long-term field experiments provide a valuable dataset for predicting changes in soil organic carbon (SOC) stocks in different agricultural systems. The RothC-26.3 model was used to simulate changes in SOC in the monoculture of spring barley (...

Soil organic matter (SOM) represents one of the largest and most important reservoirs of organic carbon in terrestrial eco-systems. The quality of SOM (e.g., content of soil organic carbon, humic substances, humic acids, fulvic acids, and HA/FA ratio) is a key factor in determining soil fertility and productivity. The loss of SOM is currently considered a detrimental form of soil degradation. The study aims to evaluate the effect of mineral fertilising (NPK), farmyard manure, cattle slurry, and digestate applications in intensively used permanent grassland. The long-term field experiments were carried out at the locality Jevíčko, region of Boskovice Furrow Malá Haná (the Czech Republic). The effect of amending soil with different organic and mineral fertilisers was studied. Qualitative parameters of SOM, soil reaction, and the content of available nutrients (N, P, K, Ca, Mg) were followed. Results showed that the control (no organic input) and the NPK variants had the lowest SOM quality. Higher SOM quality was after the farmyard manure, Slurry, and Digetsate applications. The highest acidity (indicated by the lowest values of pH/KCl) was determined in the control, NPK, Slurry, and D variants. The most favourable soil reaction and available nutrient content were after the farmyard manure application. Humic substances spectral absorption in the UV-VIS and infrared spectral ranges showed that the highest absorbance and amount of aliphatic hydrophobic components were observed after the application of farmyard manure. The multi-criteria statistical evaluation, including principal component analysis and factor analysis, confirmed that amending soil with farmyard manure and slurry resulted in an increase in humic substances content and improved SOM quality.

Global carbon storage in soils is widely discussed today because of climate uncertainty and maintaining sustainable agricultural production. Human intervention in agricultural or energy production poses many changes in soil management, which highly affects soil quality/health. Permanent grasslands fulfil a wide range of ecosystem functions and have a high potential for increasing arable land. Today, grasslands are becoming more and more intensively used, fertilized and disturbed. Optimizing their management is essential to maintain a resilient and stable ecosystem. The produced biomass is used as a forage or for energy production. We aimed at the impact of long-term grassland liming on the total content of soil organic carbon (SOC), humic substances (CHS), and microbial biomass (Cmic). Furthermore, soil reaction and available nutrient content were evaluated. Soil samples were collected from a split-plot field experiment at Mendel University in Brno (locality Kameničky). The soil was classified as Dystric Planosol Siltic, medium textured, strongly acidic, with high soil organic carbon content. The yearly liming rate was 1.4 t/ha CaO. The linkage between the soil pH, SOC, Cmic, and available nutrient content was evaluated by the multivariate exploratory techniques and regression models. Results showed that long-term liming affects both soil biota and carbon storage.

Objective. Dehydrogenase activity after the biological activation of biochar by the native soil microorganisms was studied. The main aim was to improve biochar properties by activation and make it more friendly for the soil microflora. Materials and methods. The activation was reached by aerating with the soil solution for two weeks. No special inoculum of microorganisms was applied. The following treatments in four replicates were prepared: conventional raw biochar (BR), activated biochar (BA), mineral fertilizer DAM 390 (NF), and control (C). A statistical test for comparing treatments means (Fisher p≤0.05; program STATISTICA 12.0; StatSoft software Inc., Tulsa, Oklahoma, USA) was used. Results. Statistically significant differences in the dehydrogenase activity between the treatments BR, BA, and C were found. Application of mineral fertilizers had a negative effect and increasing of nitrogen leaching was observed. Conclusions. Activating of biochar is suitable metods for impove soil biota conition compared with convention biochar.

The content of organic matter in the soil, its labile (hot water extractable carbon–HWEC) and stable (soil organic carbon–SOC) form is a fundamental factor affecting soil productivity and health. The current research in soil organic matter (SOM) is focused on individual fragmented approaches and comprehensive evaluation of HWEC and SOC changes. The present state of the soil together with soil’s management practices are usually monitoring today but there has not been any common model for both that has been published. Our approach should help to assess the changes in HWEC and SOC content depending on the physico-chemical properties and soil´s management practices (e.g., digestate application, livestock and mineral fertilisers, post-harvest residues, etc.). The one- and multidimensional linear regressions were used. Data were obtained from the various soil´s climatic conditions (68 localities) of the Czech Republic. The Czech farms in operating conditions were observed during the period 2008–2018. The obtained results of ll monitored experimental sites showed increasing in the SOC content, while the HWEC content has decreased. Furthermore, a decline in pH and soil´s saturation was documented by regression modelling. Mainly digestate application was responsible for this negative consequence across all soils in studied climatic regions. The multivariate linear regression models (MLR) also showed that HWEC content is significantly affected by natural soil fertility (soil type), phosphorus content (−30%), digestate application (+29%), saturation of the soil sorption complex (SEBCT, 21%) and the dose of total nitrogen (N) applied into the soil (−20%). Here we report that the labile forms (HWEC) are affected by the application of digestate (15%), the soil saturation (37%), the application of mineral potassium (−7%), soil pH (−14%) and the overall condition of the soil (−27%). The stable components (SOM) are affected by the content of HWEC (17%), soil texture 0.01–0.001mm (10%), and input of organic matter and nutrients from animal production (10%). Results also showed that the mineral fertilization has a negative effect (−14%), together with the soil depth (−11%), and the soil texture 0.25–2 mm (−21%) on SOM. Using modern statistical procedures (MRLs) it was confirmed that SOM plays an important role in maintaining resp. improving soil physical, biochemical and biological properties, which is particularly important to ensure the productivity of agroecosystems (soil quality and health) and to future food security.