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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. [ABSTRACT FROM AUTHOR]

Background and Aims: Bioremediation of soils contaminated with metal(loid)s is an attractive research area due to its sustainability and economic benefits. In the Slovak Republic, there are several abandoned mines containing high concentrations of arsenic (As) and antimony (Sb). This calls for new options for removing these hazardous metalloids from contaminated substrates. Studies on bioleaching of soils co-contaminated with both metalloids are very rare. This study aimed to test the effectiveness of bioleaching of soils heavily co-contaminated with As and Sb (up to 1463 mg.kg–1 and 5825 mg.kg–1, respectively) at a former stibnite mining site (Poproč, eastern Slovakia) through biostimulation and bioaugmentation. Methods: Bioleaching of As and Sb from four soils was induced by biostimulation of autochthonous microflora with Sabouraud medium (SAB) and SAB+glucose, and bioaugmentation of the soil with bacterial strains Cupriavidus oxalaticus and Cupriavidus metallidurans. Soil samples were subjected to determination of physico-chemical properties, microbiological parameters, and additional mineralogical analysis. Results: An inverse relationship between the total metalloid concentration and the microbial diversity was confirmed. In experiments with Cupriavidus metallidurans and Cupriavidus oxalaticus, mean bioleached As fractions were 37.6% and 41.3%, while Sb bioleaching was significantly lower, ranging between 17.0–26.2%. The mean bioleached fraction of As and Sb using SAB was 40.7% and 14.4%, respectively. The addition of glucose to SAB increased As bioleaching (50.7%) but not that of Sb. Conclusion: Collectively, the results highlighted a role of microorganisms in the mobility of metalloids in soils with their prospective applications in remediation of contaminated sites. [ABSTRACT FROM AUTHOR]

This paper investigates the differences in some metabolites using Biolog FF Microplate™ system and the production of organic acids such as β-hydroxybutyric, p-hydroxyphenylacetic, and others. Another group of organic acids such as gluconic, oxalic and citric acid were studied during cultivation in a liquid medium. Four different Aspergillus niger (An) wild type strains were used as a model organism. Three strains, from the Banská Štiavnica – Šobov (An – Š), Pezinok (An – P) and Slovinky (An – Sl) localities were isolated from contaminated old mining areas with soil with ultra acidic to strong alkaline reactions. The fourth strain isolated from the Gabčíkovovo (An – G) locality was used for comparative purposes. According to the RAMP analysis, the strains are clustered into two groups, An – Š and An – P (similarity 82%), An – G and An – Sl (similarity 64%) which correlates with the pH values of the original environment. However, significant differences were found in metabolic processes in the reaction with a wide range of organic acids. In general, the reactions with D-lactic acid and D-malic acid correlate with the results of the RAMP analysis of fungal genotype similarities, the An – Š and An – P strains had an identical negative reaction, and an identical positive reaction was found in the An – Sl and An – G strains. During incubation the wild-type strains produced substantial amounts of gluconic acid, oxalic acid and small amounts of citric acid. The appearance and accumulation of organic acids was found to be highly pH dependent with the most active strain isolated from an ultra-acidic environment. The comparative strain differs entirely in the production of oxalic acid.This paper investigates the differences in some metabolites using Biolog FF Microplate™ system and the production of organic acids such as β-hydroxybutyric, p-hydroxyphenylacetic, and others. Another group of organic acids such as gluconic, oxalic and citric acid were studied during cultivation in a liquid medium. Four different Aspergillus niger (An) wild type strains were used as a model organism. Three strains, from the Banská Štiavnica – Šobov (An – Š), Pezinok (An – P) and Slovinky (An – Sl) localities were isolated from contaminated old mining areas with soil with ultra acidic to strong alkaline reactions. The fourth strain isolated from the Gabčíkovovo (An – G) locality was used for comparative purposes. According to the RAMP analysis, the strains are clustered into two groups, An – Š and An – P (similarity 82%), An – G and An – Sl (similarity 64%) which correlates with the pH values of the original environment. However, significant differences were found in metabolic processes in the reaction with a wide range of organic acids. In general, the reactions with D-lactic acid and D-malic acid correlate with the results of the RAMP analysis of fungal genotype similarities, the An – Š and An – P strains had an identical negative reaction, and an identical positive reaction was found in the An – Sl and An – G strains. During incubation the wild-type strains produced substantial amounts of gluconic acid, oxalic acid and small amounts of citric acid. The appearance and accumulation of organic acids was found to be highly pH dependent with the most active strain isolated from an ultra-acidic environment. The comparative strain differs entirely in the production of oxalic acid.This paper investigates the differences in some metabolites using Biolog FF Microplate™ system and the production of organic acids such as β-hydroxybutyric, p-hydroxyphenylacetic, and others. Another group of organic acids such as gluconic, oxalic and citric acid were studied during cultivation in a liquid medium. Four different Aspergillus niger (An) wild type strains were used as a model organism. Three strains, from the Banská Štiavnica – Šobov (An – Š), Pezinok (An – P) and Slovinky (An – Sl) localities were isolated from contaminated old mining areas with soil with ultra acidic to strong alkaline reactions. The fourth strain isolated from the Gabčíkovovo (An – G) locality was used for comparative purposes. According to the RAMP analysis, the strains are clustered into two groups, An – Š and An – P (similarity 82%), An – G and An – Sl (similarity 64%) which correlates with the pH values of the original environment. However, significant differences were found in metabolic processes in the reaction with a wide range of organic acids. In general, the reactions with D-lactic acid and D-malic acid correlate with the results of the RAMP analysis of fungal genotype similarities, the An – Š and An – P strains had an identical negative reaction, and an identical positive reaction was found in the An – Sl and An – G strains. During incubation the wild-type strains produced substantial amounts of gluconic acid, oxalic acid and small amounts of citric acid. The appearance and accumulation of organic acids was found to be highly pH dependent with the most active strain isolated from an ultra-acidic environment. The comparative strain differs entirely in the production of oxalic acid. [ABSTRACT FROM AUTHOR]