BOOK OF ABSTRACTS 235 IHSS&IWA26 / BRNO / CZECHIA / 23–28 August 2026 Hall A Poster Session / Environment, Agriculture, and Forestry P4.12 Organic Matter in Soils Heavily Affected by Emissions from Magnesite Processing Plants Nora Polláková1, Vladimír Šimanský1, Jerzy Jonczak2 1 Slovak University of Agriculture in Nitra, Faculty of Agrobiology and Food Resources, Institute of Agrochemistry and Soil Science, Tr. A. Hlinku 2, 949 76 Nitra, Slovak Republic, e-mail: nora.pollakova@uniag.sk 2 Warsaw University of Life Sciences-SGGW, Poland Slovakia has been mining magnesite for a long time and is a significant processor of magnesite ore, with a history dating back to 1923 in Jelšava and 1934 in Lubeník. In 1958, the shaft processing technology was replaced by more efficient rotary furnaces, which greatly increased the production of Mg-rich alkaline dust in the area. In 1984, effective filters were installed [1], significantly reducing the release of alkaline Mg-rich dust, which, according to Šály and Minďáš [2], contained 35%–50% amorphous MgO and 10%–20% other minerals (such as periclase, dolomite, and calcite). However, the degradation of soil and the environment by alkaline dust is long-lasting and leads to decreased enzymatic activity of soil microorganisms [3] and reduced plant biodiversity [4]. The aim of this work was to investigate selected chemical soil properties, as well as the content and quality of organic matter in soil affected by alkaline, Mg-rich dust emitted from magnesite processing plants in Lubeník and Jelšava. Soil properties were investigated in 14 composite samples collected according to the intensity of solid emission deposition, which depends considerably on the proximity to the Mg-processing plants and the direction of the predominant winds carrying alkaline emissions. Results showed that the highest magnesium content (total up to 64.72 g kg-1, available up to 17.39 g kg-1) was found at sampling sites near both Mg-processing plants. A higher content of total, and especially available, Mg caused a significant increase in soil pH H2O (up to 9.39) and resulted in a low available Ca:Mg ratio, which worsened conditions for vegetation growth. This led to a significantly lower content of both labile soil organic matter (hot watersoluble carbon, labile organic carbon) and stable, humified organic matter (humus substances and fulvic acids). In contrast, associated calcium promoted the formation of humic acids as a highly condensed, stable fraction of soil organic matter, thus enhancing humus quality, as indicated by a significantly increased humic to fulvic acids ratio. The results showed that the content and quality of soil organic matter are significant indicators of soil degradation caused by alkaline magnesium immissions.
RkJQdWJsaXNoZXIy NDA4Mjc=