Effect of Soil Samples Preparation on Their Thermal Hydrophysical Properties and Allelotoxicity

• Published in: Eurasian soil science Vol. 55; no. 3; pp. 330 - 338
• Main Authors: Potapov, D. I., Shvarov, A. P., Gorepekin, I. V., Salimgareeva, O. A., Fedotov, G. N.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.03.2022; Springer; Springer Nature B.V
• Subjects: Aggregation; Analysis; Autoclaving; Decomposing organic matter; Drying; Earth and Environmental Science; Earth Sciences; Electric properties; Electrical conductivity; Electrical resistivity; Gels; Geotechnical Engineering & Applied Earth Sciences; Heating; Humus; Hydrogeology; Hydrophobicity; Hygroscopic water; Moisture content; Soil aggregates; Soil conductivity; Soil investigations; Soil moisture; Soil Physics; Soil properties; Soil stability; Soil structure; Soil water; Thermal diffusivity; Thermal properties; Water; Water stability; Wetting; water stability of soil aggregates; filtration; hydrophilic–hydrophobic properties of soils; soil allelotoxicity; water retention curve; gel structures; soil organic matter; soil thermal diffusivity
• ISSN: 1064-2293; 1556-195X
• DOI: 10.1134/S1064229322030115

Changes in the properties of soil samples during drying or heating are known. However, the reasons for them have remained unclear up to this time. Our study aims to clarify the processes occurring during drying–wetting and heating of wet soils by the study of the changes in the soil properties. Soddy-podzolic soils were investigated. The influence of soil drying on the water-holding capacity in the capillary and hygroscopic water ranges of the water retention curve (WRC), hydraulic conductivity, water stability of soil aggregates, and allelotoxicity has been studied. The impact of heating of wet soils on the hydrophilic-hydrophobic properties, allelotoxicity, electrical conductivity of soil water extracts, and thermal diffusivity of wet soils has also been analyzed. It is shown that soil particles become hydrophobized during drying–wetting cycles and during autoclaving, which leads to an increase in the content of allelotoxins accessible to plants. To explain the obtained data, the concept of transformation of gel structures covering and binding soil particles during drying or heating has been used. The applied model includes an assumption that primary particles of humus substances having a diphilic surface and forming fractal clusters can interact with one another in the primary and secondary minima of aggregation.