In recent years, the importance of soil health for ecosystem functions has come further into the scientific focus (Lehmann et al., 2020). Especially after severe ecosystem disturbances, soil formation has to start anew. Such disturbances, which reset ecosystem development to the starting point, can be of natural (volcanoes, mobile sand dunes, floods, glaciers) (La Farge et al., 2013; Lan et al., 2014) or human origin (post-mining landscapes, military training areas, agricultural lands) (Belnap et al., 2007; Schaaf et al., 2011). In these young ecosystems, the interactions between the initial colonizers, the inorganic matter, and the subsequent biogeochemical processes are an important prerequisite for the development of elemental fluxes, soil genesis, and thus for further ecosystem development. In addition to pioneer plants, photoautotrophic and heterotrophic microorganisms play a major role in the colonization of the freshly deposited sediment, regolith, or disturbed soil material. Biological soil crusts (BSCs) develop when various combinations of diminutive bacteria, terrestrial algae, fungi, lichens, and/or bryophytes occupy the upper few millimeters of the soil or regolith.