Soil organic matter, in a narrower sense, humic substances, has been subject of research for several centuries. Nevertheless, questions on its formation or character still have not been resolved. The traditional polymer theory seems to be replaced in the last two decades by supramolecular views, lately claims on the non-existence of the humic substances have become rampant, looking at the soil organic matter as a complex mixture of products at various degrees of the decomposition of decaying original plant or animal matter. Further, it can contain also metabolic products of the soil microorganisms. After additional but in-depth literature search, the PhD study will be focused on one of or both following partial goals. 1) Thermodynamics and kinetics of the soil metabolic reactions with special regard to the synthesis of polyketides and their potential incorporation into the principal structural unit of the soil organic matter. 2) Colloid structures in the soil solution or in the soil aqueous leachates, their size, stability, diffusion behavior, aggregate character, chemical composition. Just hydrocolloids and water-soluble molecules are accessible to plants and thus are among key factors enabling and controlling their development and growth. Results will be evaluated also from the point of view of the current discussion on the origin, character, and stability of soil organic matter.
Tutor prof. Ing. Miloslav Pekař, CSc.
Deadline: 30. 4. 2023
Application and contacts: https://www.fch.vut.cz/uchazeci/prijimacky/d