Gabriella RÉTHÁTI 1 -Viktória LABANCZ1 - László TOLNER1 - Zoltán SZALAI2 -László ALEKSZA1

1Institute of Environmental Sciences, Faculty of Agricultural and Environmental Sciences, Szent István University, H-2100 Gödöllő, Páter Károly str. 1.

2Institute of Geography and Earth Science, Faculty of Science, Eötvös Loránd University


The organic materials, especially the complex structural humic substances that are made of acid-characteristic polymers, are key elements of soils. Despite their small quantity, humic substances have beneficial effects on soil nutrient management, development of optimal soil structure, regulation of soil temperature, and proper water management. Humic substances are much more stable than the original organic materials, however, the adverse environmental effects and cultivation can easily disrupt the sensitive equilibrium of humus formation. To reduce these negative processes an environmental friendly method has been developed in soil carbon management, which impact has already been studied but on humic substances interaction-analysis are still in the initial phase.

This study is based on the examination of soil and compost samples with different quality. These measurements are supplemented by samples with various origin and quality, with high organic carbon content. During our examinations, optical density of different brown forest soils, composts, and pyrolyzed organic materials were determined between 465 and 665 nm wavelength. We drew our conclusions about the humus fractions of the samples based on the E4/E6 ratio, which is the ratio of the two obtained extinctions.  

Keywords: E4/E6 ratio, compost, charcoal, bonechar, biochar