20.11.2024: Minsu Kim (Graz, Austria): Phase transition dynamics of biopolymers in soils and their impact on soil-atmosphere interaction, HS 02.11, Institut für Biologie, Bereich Zoologie, Universitätsplatz 2, 13:15 Uhr
In this talk, I will propose a theoretical framework that examines the impact of active soil microorganisms on modifying soil pore environments. The primary focus will be on the microbial contribution to the development of soil functionality and biogeochemical cycles across different scales. Using biological soil crusts as a key example, I will demonstrate how the carbon and water storage capacity of soils can be improved through the phase transition dynamics of microbially produced biopolymers, specifically extracellular polymeric substances (EPS). This discussion will also consider how soil wetting and drying cycles trigger repetitive EPS phase transitions, contributing to the gradual development of a structural memory associated with the active synthesis of microbial biopolymers. By integrating a mechanistic model with field and laboratory observations, I will highlight the crucial role of EPS phase transition dynamics in shaping soil-atmosphere exchanges and surface energy balances.